X, n.
plural X's, Xs Hear pronunciation/ˈɛksɪz/, the twenty-fourth letter of the modern and the twenty-first of the ancient Roman alphabet, corresponding in form and position to the Greek Χ. The early Greek forms ?? represented the aspirated voiceless velar /kh/ in the Ionian alphabet, and /ks/ in the Chalcidian alphabet. (In the former, /ks/ was denoted by ?, in the latter, /kh/ was denoted by ?.) Χ was adopted by the Latins with the value /ks/ from the Greek alphabet introduced into Italy. The ancient Roman name of the letter was ix, which is that given by Ælfric in his Grammar (c1000). Words having initial x (pronounced as z) in English are nearly all of Greek origin; a few, as xebec, Xerez, have x representing early Spanish x (now j). In Old English x was used medially and finally as a variant spelling of cs (whether original or standing for sc), e.g. æx, eax = æcus, acus, æsc axe n.1, áxian = ácsian, áscian to ask v., fixas, plural of fisc fish n.1, fixian = fiscian to fish v.1, waxan = wascan to wash v. Other variants are cx, hx, xs, cxs, hxs, as meohx, micxen mixen n., axsan ash n.2 Similar spellings occur in the Cotton MS. of Cursor Mundi, e.g. flexs(s flesh, wexs wash, fixses fishes; the same MS. has the unexplained spellings fux(o)l, foux(u)l, etc. of fowl n. In East Anglian texts of the 14th to the 16th century x is frequently written for initial sc, sch in xal shall, xuld should; xsal also is found in the Paston Letters; instances of other words so written are only occasional, e.g. xad shed (past participle), xowyn shove, xuldrys shoulders. Initial x stands for sh (or s) in early forms of some oriental words, as xerif shereef n. (after early Spanish xerife), xaraffe, -aff saraf n., and Xinto Shinto n. Other temporary uses of x, but with its normal value /ks/, are found in the once general axes, axis access n., hunx hunks n., and the less common exelent excellent adj. and adv., exite excite v.; on the other hand pox = pocks has become permanent, and sox has been adopted, originally in the hosiery trade, as a convenient shortening of socks. The phonetic values of x in English are three, of which the commonest is /ks/, as in axis Hear pronunciation/ˈæksɪs/, buxom Hear pronunciation/ˈbʌksəm/, doxology Hear pronunciation/dɒkˈsɒlədʒɪ/, excuse Hear pronunciation/ɪkˈskjuːs/, expense Hear pronunciation/ɪkˈspɛns/, oxen Hear pronunciation/ˈɒks(ə)n/, proximity Hear pronunciation/prɒkˈsɪmɪtɪ/, tax Hear pronunciation/tæks/. The pronunciation of the prefix ex- followed by a vowel or h varies according as it bears the stress or not, the general rule being that ˈex— = Hear pronunciation/ɛks/ and ex—ˈ = Hear pronunciation/ɪɡz/, as exile Hear pronunciation/ˈɛksaɪl/, exact Hear pronunciation/ɪɡˈzækt/, exhort Hear pronunciation/ɪɡˈzɔːt/; but there is considerable variety in individual words and individual usage: see ex- prefix1 1a note. The same general principle governs the pronunciation of anxious Hear pronunciation/ˈæŋkʃəs/, anxiety Hear pronunciation/æŋɡˈzaɪɪtɪ/, luxury Hear pronunciation/ˈlʌksjʊərɪ/Hear pronunciation/ˈlʌkʃərɪ/, luxurious Hear pronunciation/lʌɡˈzjʊərɪəs/Hear pronunciation/lʌɡˈʒʊərɪəs/ Alexander Hear pronunciation/ælɪɡˈzɑːndə(r)//-æ-/, Alexandrine Hear pronunciation/ælɪɡˈzɑːndrɪn//-æ-/; but here also individual usage varies. The third value /z/, arising from a reduction of /ɡz/, is given in all cases to initial x, as Xerxes Hear pronunciation/ˈzɜːksiːz/; this value is shown in many instances in the 17th and 18th centuries by the spelling with z, as Zanthian, zebeck, Zerez, and instances are not uncommon in the 19th century of zantho- and zylo- for xantho- and xylo-; early examples are Zanctus Xanthus (Lydg. Troy Bk. ii. 731 rubric, 15th cent.), zyphe xiph n. (1572). Cf. Santippa Xanthippe (Chaucer), Cerses Xerxes (Wyntoun Chron., S.T.S., III. 54). A similar reduction of x took place in French:x, if he be the fyrste letter of a worde, as xenotróphe, xylobalsóme, whiche they sounde but s, sayenge senotrophe, sylobalsome, for they can nat gyve x, whiche is also a greke letter, is true sownde. (Palsgr. Esclarc. (1530) i. xxv.)
I. The letter, its sound or shape; also denoting serial order.
1.
a. The letter or its sound. x-height (rarely X-height (Typography), the height of a printed lower-case x, esp. as representative of the size of the fount to which it belongs.
c1000 Ælfric Gram.
(Z.)
6
x ana ongynð of þam stæfe i æfter uðwitena tæcinge.
1530 J. Palsgrave Lesclarcissement 38
Note that x shall never be sounded in frenche lyke as he is in latyn, or as we wolde do in our tonge, in no wyse, but lyke an z.
c1620 A. Hume Of Orthogr. Britan Tongue
(1870)
i. iv. §7
The top of the tongue stryking on the inward teeth formes d, l, n, r, s, t, and z... The midle tongue stryking on the rouf of the mouth formes the rest, c, g, k, j, q, and x.
a1637 B. Jonson Eng. Gram. i. iv, in Wks.
(1640)
III
X, Is rather an abbreviation, or way of short writing with us, then a Letter..It begins no word with us, that I know, but ends many.
1735 C. Middleton Diss. Origin Printing Eng. 7
I take the Date in question to have been falsified originally by the Printer,..and an x to have been dropt..in the Age of its Impression.
a1845 R. H. Barham Lord of Thoulouse in Ingoldsby Legends
(1847)
3rd Ser. 202
His cap, and his queer cloak all X's and Izzards.
a1849 E. A. Poe X-ing a Paragrab in Wks.
(1856)
IV. 264
When the exigency does occur, it almost always happens that x is adopted as a substitute for the letter deficient.
1864 C. Boutell Heraldry Hist. & Pop.
(ed. 3)
xxi. 360
Az., on a cross arg. the letter X sa.
1878 W. J. Cripps Old Eng. Plate 110
Much of the old..plate of the sixteenth and seventeenth centuries that is still to be found in the counties of Devon and Cornwall bears the old Exeter mark, which was a large Roman capital letter X crowned.
1945 J. C. Tarr Printing To-day 177
x-height, the height of lower-case letters (excluding descenders and ascenders), i.e. the height of a lower-case x.
1959 L. M. Harrod Librarians' Gloss.
(ed. 2)
, 99
Descender,..that part which extends below the ‘X’ height.
1964 P. A. D. MacCarthy in D. Abercrombie et al. Daniel Jones 160
Any attempt to preserve traditional usage by having only x-height letters for vowels.
1978 J. Lewis Typogr. ii. 79
Typefaces with a large x-height are more suitable for an age accustomed to reading sans serif signs... VIP Palatino is another large x-height typeface.
c1000—1978(Hide quotations)
b. The letter considered with regard to its shape: chiefly attributive and in other combinations. Hence identified with a cross. X's and O's: the game of noughts and crosses. X chair, a chair in which the underframe resembles the letter X in shape; so X-frame (usually attributive).
1545 Bibliotheca Eliotæ
Decussis..is also a fourme in any thynge representynge the letter X, whiche parted in the myddell maketh an other figure called Quincunx, V.
1769 in C. Welsh Bookseller of Last Cent. 354
Those [books] with an X.
1798 Hull Advertiser 28 July 2/1
Chairs in sets..with W tableau and X backs.
1837 L. Hebert Engin. & Mech. Encycl. II. 876
The said pin traverses the X groove from side to side.
1839 Penny Cycl. XV. 176/1
Suppose a cross like an X or V to be cut out of brass-plate.
1861 H. Hagen Synopsis Neuroptera N. Amer. 213
An x-shaped spot.
1866 R. D. Blackmore Cradock Nowell xii
The boy leaped the new X fence very cleverly.
1893 F. C. Selous Trav. S.-E. Afr. 402
I will write your name..on the paper..and you must make an ‘x’ behind your name.
1894 S. R. Crockett Raiders 92
It wasna playing at x's and o's to be steering for that crossbones of a Dutchman.
1899 J. L. Williams Stolen Story 54
Billy, reaching the end of the page, made a double X mark to show that it was the end of the story.
1904 P. Macquoid Hist. Eng. Furnit. iii. 52
It is a very common error to assign all these ‘X’ chairs to foreign importation.
1911 P. Bridges Green Wave of Destiny xiv. 211
There was just room between the humps for two narrow sacks placed X-wise.
1918 G. L. Hunter Italian Furnit. & Interiors
(1920)
I. p. iv
Of Italian chairs there are more types than were until recently known to exist:..folding ‘X’ chairs of the type sometimes called ‘Savonarola’, wonderful ‘Dante’ chairs.
1945 Burlington Mag. May 110/2
These X chairs throughout the sixteenth century, when made for the homes of the wealthy, were covered with rich cloths of gold, velvets, and silks.
1955 R. Fastnedge Eng. Furnit. Styles i. 33
(caption)
Arm chair of X-frame construction... Early seventeenth century.
1961 L. G. G. Ramsey Connoisseur New Guide Antique Eng. Furnit. 20
Another form of chair, of different origin from the boxchair, was the X chair... Both chairs are assigned to about the same period—that is the middle of the sixteenth century.
1976 Country Life 27 May (Suppl.) 486/1
Late 18th century wheel-back armchairs with saddle seats and X-frame legs.
1545—1976(Hide quotations)
c. Used like other letters of the alphabet to denote serial order, as in the signatures of the sheets of a book, the batteries of the Royal Horse Artillery, etc.
d. Used to mark a location on a map or the like; esp. in X marks the spot and variants.
1813 M. Edgeworth Let. 16 May
(1971)
59
The three crosses X mark the three places where we were let in.
1918 J. M. Barrie Echoes of War 5
In the rough sketch drawn for to-morrow's press, ‘Street in which the criminal resided’..you will find Mrs. Dowey's home therein marked with a X.
1928 R. A. Knox Footsteps at Lock iv. 36
I wish I could be there, to see you diving in the mud on the spot marked with an X.
1968 B. Norman Hounds of Sparta ix. 64
A message from our alcoholic friend. X seems to mark the spot where he lives.
1813—1968(Hide quotations)
II. Symbolic uses.
2.
a. The Roman numeral symbol for ten (or †tenth); so xx = twenty (in early use also for ‘score’, as iijxx = ‘three score’, 60; also occasionally xxti = Latin viginti), xxx, occasionally xxxty = thirty, etc.
c1000 Anglo-Saxon Chron. ann. 409
(Parker MS.)
Þæt wæs embe .xi. hund wintra & x. wintra þes þe heo getimbred was.
a1400 Wyclif's Bible Prol.
(1850)
I. 17
There weren not left..no but v. hundrid horsmen, and x. charis, and x. thousind of footmen.
▸
c1426 J. Audelay Poems
(1931)
70
Ȝour x comawndmentis ȝe most con.
c1450 Mirour Saluacioun (Roxb.) 146
The feest of kyng Aswere was ixxx dayes duryng.
?1478 W. Paston in Paston Lett. & Papers
(2004)
I. 649
He seythe ye be xxtis. in hys dette.
1481 Howard Househ. Bks. (Roxb.) 9
For j.m. jc iiijxx maryners.
1481–90 Howard Househ. Bks. (Roxb.) 451
The nombir of the horse ys vijxx iij.
1488 Henry's Wallace v. 909
Xxxty with him off nobill men at wage.
1489 M. Paston in Paston Lett. & Papers
(2004)
I. 669
Wretyn at London þe x day of Februare.
1535 in S. Tymms Wills & Inventories Bury St. Edmunds
(1850)
126
To my valentyn Agnes Illyon xs.
1537 T. Cromwell in R. B. Merriman Life & Lett. T. Cromwell
(1902)
II. 53
Frome London the xth daye of Apryll.
1638 J. Ford Fancies iii. 35
If my watch keep faire decorum, Three quarters have neere past the figure X.
1686 Bp. G. Burnet Some Lett. conc. Switzerland iv. 241
Pope Leo the Xs time.
c1000—1686(Hide quotations)
†b. xr: abbreviation of December. Obsolete.
1624 W. Aston in G. Goodman Court King James I
(1839)
(modernized text)
II. 369
Madrid, 24 of Xr 1624.
1624—1624(Hide quotations)
c. x: a ten-dollar note. XX: a twenty-dollar note. U.S. colloquial.
1837 Knickerbocker Mag. 9 96
My wallet..distended with V's and X's to its utmost capacity.
1883 F. M. Crawford Dr. Claudius xx
The Custom-House officials..who know the green side of a XX.
1837—1883(Hide quotations)
3.
a. In Algebra and Higher Mathematics used as the symbol for an unknown or variable quantity (or for the first of such quantities, the others being denoted by y, z, etc.); spec. in Geometry, the sign for an abscissa, or quantity measured along the principal axis of co-ordinates (hence called the †axis of x; now always x-axis; also transferred). X-cut adj. (Electronics), of, pertaining to, or designating a quartz crystal cut in a plane normal to its X-axis; X-plate (Electronics), each of a pair of electrodes in an oscilloscope that control the horizontal movement of the spot across the screen. Hence allusively for something unknown or undetermined (also attributive and in combinations). See also X-ray n. and adj.The introduction of x, y, z as symbols of unknown quantities is due to Descartes ( Géométrie, 1637), who, in order to provide symbols of unknowns corresponding to the symbols a, b, c of knowns, took the last letter of the alphabet, z, for the first unknown and proceeded backwards to y and x for the second and third respectively. There is no evidence in support of the hypothesis that x is derived ultimately from the medieval transliteration xei of šay' ‘thing’, used by the Arabs to denote the unknown quantity, or from the compendium for Latin res ‘thing’ or radix ‘root’ (resembling a loosely-written x), used by medieval mathematicians.
1660 J. Moore Arithm. ii. i. §19. 16 (Algebra)
Note alwayes the given quantities or numbers with Consonants, and those which are sought with Vowels, or else the given quantities with the former letters in the Alphabet, and the sought with the last sort of letters, as z y x, &c. lest you make a confusion in your work.
1709 J. Ward Young Mathematician's Guide
(1713)
iv. iii. 380
Let y = As the Abscissa, and z = SP, put x = Aa the Distance between the two Semi-ordinates; which we suppose to be infinitely near each other.
1726 E. Stone New Math. Dict. at Conoid
If a be equal to the Transverse Axis of the Hyperbola, generating a Conoid, and x be the Heighth of the Conoid, or the Absciss of the Hyperbola.
1771 Encycl. Brit. II. 269
The equation of any curve, is an algebraic expression, which denotes the relation betwixt the ordinate and abscissa; the abscissa being equal to x, and the ordinate equal to y.
1839 Penny Cycl. XIII. 175/2
[article Kant] What is that unknown principle (= X) on which the understanding relies, when of the subject A it finds a foreign predicate B, and believes itself justified in asserting their necessary connexion?
1885 J. Casey Treat. Analyt. Geom. ii. 22
If the equation of the line contains no x, it is parallel to the axis of x; and if it contains no y, it is parallel to the axis of y.
1886 W. B. Smith Elem. Co-ordinate Geom. i. i. 10
OX, OY, are called Co-ordinate Axes, or axes of X and Y, or X- and Y-axes.
1893 F. W. L. Adams New Egypt 29
The x of the Egyptian equation being pretty obviously the Egyptian people.
1898 W. T. Stead in Daily News 8 Nov. 5/4
What manner of man is its author? He is the X in the equation.
1898 A. Lang Making Relig. ii. 15
Research in the X-region is not a new thing under the sun.
1903 J. B. Greenough & G. L. Kittredge Words v. 53
To make fun of the x's and y's of the algebraist.
1906 Daily Chron. 12 May 4/3
There is ‘a wholesome distrust,’ says Professor Ewing, ‘of what may be called x-chasing.’
1929 Internat. Critical Tables
(National Res. Council (U.S.))
VI. 211/1
The z-axis coincides with the crystallographic c-axis of 3-fold symmetry, the y-axis is ⊥ to a face of the hexagonal first order prism, and, in dextro crystals, the + direction of the x-axis is outward through one of the faces..of the trigonal pyramid.
1930 W. G. Cady in Proc. IRE 18 2139
We consider first the manner of indicating the orientation of the more common ‘cuts’ [in quartz crystals]... In the first case, we have the cut variously referred to in the literature as ‘Curie cut’..or ‘normal cut’... However, a still more concise term would be the ‘X-cut’, denoting a plate the normal to whose face, and hence for which the applied electric field, is parallel to an X-axis. Similarly, the term ‘Y-cut’ would apply to the second type of quartz plate, which has hitherto been referred to as the ‘30-deg. cut’ or ‘parallel cut’.
1933 J. H. Morecroft Electron Tubes xii. 337
The velocity of [compression] wave travel is different in the Y axis direction from that along the X axis.
1933 J. H. Morecroft Electron Tubes xii. 338
An X-cut plate has a negative temperature coefficient, i.e. the frequency of oscillation decreases as the temperature rises... The Y-cut plates have a positive coefficient.
1934 J. H. Reyner Television vii. 71
We then apply a suitable periodic voltage across the X plates which spreads the trace-out at right angles and produces a pattern on the screen.
1945 Electronic Engin. 17 723
These two equations define the components of the velocity of the spot along the X and Y axes.
1946 Electronic Engin. 18 23/1
A D.C. connexion must be made between the output of the time base and the X plates of the tube.
1969 Funk & Wagnalls Dict. Electronics 170/1
X-axis, in a quartz crystal, a reference axis chosen so as to connect two opposite vertices of its hexagonal cross section; one of the axes showing the greatest electrical activity.
1973 S. K. Stein Calculus & Analyt. Geom. ii. 26
Far to the right and to the left the graph gets closer and closer to the x axis without ever touching it.
1978 D. T. Rees Cathode Ray Oscilloscope 9
A voltage applied to the X-plates will deflect the beam sideways.
1982 IEEE Trans. Industr. Electronics 29 158/1
The rotated X-cut orientation has been found to be optimum from the viewpoint of its frequency versus temperature and pressure characteristics.
1983 V. M. Ristic Princ. Acoustic Devices vi. 180
The relationship between the natural axes a, b, c and the crystallographic axes X, Y, Z must be known in order to use the proper constants. These relationships, for each crystal system, have been adopted by convention. Various piezoelectric, elastic, and other constants of a particular crystal specimen are evaluated in terms of X, Y, Z axes.
1660—1983(Hide quotations)
b. Hence used attributively as an indeterminate numeral adjective = ‘an unknown number of..’ Chiefly humorous.
1847 W. M. Thackeray Vanity Fair
(1848)
xi. 85
The black porker's killed—weighed x stone.
1904 Brit. Med. Jrnl. 15 Oct. 965
In the union of egg and sperm we witness the joining together of but two sets of characters and not that of ‘x’ sets derived from as many ancestors.
1847—1904(Hide quotations)
c. Put for a person's name when unknown or left undetermined. Also X. Y. (See also 5.)
1797 in Corr. Pinckney, Marshall & Gerry
(1798)
36
We have promised Messrs. X. and Y. that their names shall in no event be made public.
1821 J. Bentham Elements Art of Packing 125
As to Mr. x, I borrow, on this occasion for his use, one of the names employed by mathematicians for the designation of their unknown quantities.
1848 W. M. Thackeray Ballads of Policeman X Bow Street (ad fin.)
Pleaceman X 54.
1848 W. M. Thackeray Ballads of Policeman X Three Christmas Waits 1
My name is Pleaceman X.
1853 E. Bulwer-Lytton My Novel IV. xii. iv. 22
The house-steward..was in fact the veritable XY of the Times [newspaper], for whom Dick Avenel had been mistaken.
1857 C. Dickens Little Dorrit ii. xii. 427
The son of P. Q...whom we would call X. Y.
1873 H. Drummond New Evangelism & Other Addr.
(1899)
199
X won't be preached to along with Y and Z and Q; that won't do X any good, for he thinks it is all meant for Y, Z, and Q.
1899 O. Seaman In Cap & Bells
(1900)
47
For terror of the Law and him that waits Outside, the unknown X, to hale us hence.
1901 E. Glyn Visits of Elizabeth
(1906)
70
You feel obliged to ask the X's, the Y's, and the Z's from duty, and so you do... This is the kind of assortment that arrives: Papa X, Mamma X, and two girl X'es; Papa Y, Mamma Y, and Master and Miss Y; Papa Z, Mamma Z, Aunt Z, and Midlle. Z—such a party!
1797—1901(Hide quotations)
d. In wireless telegraphy (also in combination x-stopper): see quot. 1906.
1906 J. A. Fleming Princ. Electr. Wave Telegr. ix. 611
The electric discharges due to atmospheric electricity create electromagnetic waves of an irregular type, which interfere with wireless telegraphy by causing irregular signals. These are technically termed X's... Means have been devised for sifting out the waves due to these irregular atmospheric disturbances... One of these devices, due to Mr. Marconi, has received the name of an X-stopper.
1906—1906(Hide quotations)
e. Genetics. (Now always as a capital.) [First used in German by H. Henking 1891, in Zeitschr. f. wissensch. Zool. LI. 706.] The symbol of the X chromosome n. So X-linked adj. (stress variable) being or determined by a gene that is carried on the X chromosome.
1902 T. H. Montgomery in Trans. Amer. Philos. Soc. 20 177
One of these three [chromosomes of Protenor belfragei], that designated x in Figs. 119–123, imposes by its relatively very large volume... We shall call this the ‘chromosome x’.
1902 Biol. Bull. Dec. 29
(caption)
All the chromosomes including the accessory (x), show indications of a longitudinal split.
1909 E. B. Wilson in Science 8 Jan. 57/1
In all the species half the spermatozoa are characterized by the presence of a special nuclear element which I shall call the ‘X-element’, while the other half fail to receive this element.
1910 E. Wilson in Science Progress IV. ii. 572
If the two kinds of spermatozoa be designated as the ‘X-class’ and the ‘Y-class’, respectively, the eggs are all of the X-class. The male may, accordingly, be designated as the heterogametic sex, the female as the homogametic.
1911 Biol. Bull. Jan. 118
The case of the aphids and phylloxerans has been the strongest argument for the hypothesis that two X chromosomes [in mosquitoes] give a female and..XY a male.
1949 C. D. Darlington & K. Mather Elements of Genetics ii. 49
The tortoiseshell cat is heterozygous for the X-linked gene, one allelomorph of which gives black, the other yellow, when homozygous.
1968 M. W. Strickberger Genetics xii. 216
In some instances, both compound X's and compound Y's may be found together in the same species. An extreme example of compound sex chromosomes occurs in the beetle Blaps polychresta, where the male has 12 X's and 6 Y's in addition to 18 autosomes.
1977 N. V. Rothwell Human Genetics iv. 83
One important point to note is that a male never passes an X-linked gene to his sons.
1983 D. J. Weatherall et al. Oxf. Textbk. Med. I. iv. 16/2
The triple X female with 47 chromosomes shows very little physical abnormality... It is possible that only one X is working in any cell at a given time.
1983 J. R. S. Fincham Genetics ii. 72
In grasshoppers and other insects of the order Orthoptera..there is usually no Y-chromosome. The females are XX and the males just X.
1902—1983(Hide quotations)
f. x-chaser, etc.: a naval officer proficient in examinations or good at his work (see also quots. 1946 at sense 3a, 1962). slang.
1904 ‘Vanderdecken’ Mod. Officer of Watch vi. 64
To get on at sea it is not necessary to be an X hunter, a man may be a smart officer without ever having been near enough to an X to drop salt on its tail.
1912 ‘Aurora’ Jock Scott, Midshipman i. 4
He was what we called an x catcher; in fact, he passed out of the Britannia a midshipman and was wearing his patches the day he left.
1916 ‘Taffrail’ Pincher Martin v. 71
He was an x-chaser, in that he had done remarkably well in all his different examinations.
1946 J. Irving Royal Navalese 190
X chaser, a mathematically minded man; a theoretician. Also, a navigating officer who has qualified..as the navigator of a First Class ship.
1962 A. G. Course Dict. Naut. Terms 215
X chaser, a meticulous navigator in the Royal Navy.
1904—1962(Hide quotations)
g. In the analysis of games of Bridge x represents a card between 2 and 9, inclusive.
1920 A. G. L. Owen Mod. Bridge ii. 56
A similar position is this:—Z xxx A King xx BJ 10 xx YAQ. If A leads his King, Y makes Ace and Queen.
1933 C. Vandyck Contract Contracted i. 10
x = any small card... An easy way of remembering the Kx and Qx in different suits is to think of it as the Grand Marriage.
1959 T. Reese & A. Dormer Bridge Player's Dict. 14
East holds..Kxxxx.
1972 Country Life 4 May 1119/3
The trump finesse could not gain, even if East held Q xx.
1920—1972(Hide quotations)
h. x-question (Linguistics) (see quots.).
1924 O. Jespersen Philos. Gram. xxii. 303
In the other kind of questions we have an unknown ‘quantity’... We may therefore use the well-known symbol x for the unknown and the term x-question for a question aiming at finding out what x stands for.
1957 S. Potter Mod. Ling. iii. 71
Tune 1 falls after the turn. It is used in completed statements, in direct commands, and in special or x-questions which cannot be answered by ‘yes’ or ‘no’ and which are generally introduced by an interrogative pronoun or adverb.
1964 M. Chapallaz in D. Abercrombie et al. Daniel Jones 306
X-questions, that is, questions beginning with a specific interrogative word.
1924—1964(Hide quotations)
i. Genetics. (Now written as lower case.) A symbol representing the lowest number of chromosomes which make up a genome; frequently with preceding number, designating the number of sets of these in a cell, or in each cell of an organism.
1924 Hereditas V. 144
Summarizing our results on the chromosome set in C[arex] pilulifera, we may now state that this species has 9 chromosomes (X) of which there are 3 long, 4 medium and 2 short ones.
1924 Hereditas V. 161
In Triticum Sakamura..and Sax..found one species with 14 chromosomes (2X), four species with 28 and three with 42 chromosomes.
1932 C. D. Darlington Rec. Adv. in Cytol. iii. 61
Since a zygote usually receives two similar sets of chromosomes from its two parental gametes, their number is conventionally referred to as 2n; where the chromosomes pair regularly at meiosis they therefore form n pairs. Now in a particular individual these 2n chromosomes may consist of three sets or four sets of chromosomes relative to its own parents or ancestors. In the present work, therefore, the ‘basic number’ of this ancestral set is distinguished by the sign x. Thus in Triticum vulgaer 2n = 42 and x = 7, the somatic chromosome number is therefore hexaploid (6x).
1979 A. F. Dyer Investigating Chromosomes ii. 47/2
Rosa canina (2n = 5x = 35 = AABCD).
1980 J. Schulz-Schaeffer Cytogenetics vii. 122
Very often, ploidy levels are erroneously reported for n-numbers. But the number reserved for ploidy levels is the x-number or basic genome number (x, 2x, 4x, 6x, etc.).
1924—1980(Hide quotations)
j. X factor (Military colloquial), the aspects of a serviceman's life that have no civilian equivalent; pay made in recognition of these.
1969 Second Rep. Pay Armed Forces
(Nat. Board for Prices & Incomes)
vi. 21 in Parl. Papers (Cmnd. 4079) 517
There are special conditions of employment..common to all servicemen and which.. make it more uncertain and on occasions more hazardous than the normal..employment in civilian life... The elements..constitute, what we have termed the X factor.
1979 Navy News May 48/3
The Ministry of Defence have proposed a substantial increase in the X factor across the board on the grounds that the elements that make up the justification for it have shifted to the disadvantage of the Services.
1969—1979(Hide quotations)
4. In designations of brands of ale, stout, or porter, XX or double X denotes a medium quality, XXX or treble X the strongest quality. Also in the marking of qualities of tin-plate.
1826 W. Hone Every-day Bk.
(1827)
II. 11
A lover of the best London porter and double XX.
1828 M. R. Mitford Our Village III. 204
His best double X.
1839 A. Ure Dict. Arts 1254
The following Table shows the several sizes of tin plates [and] the marks by which they are distinguished..Common, No. 1..c. 1... Two crosses, 1..xx. 1. Three crosses, 1..xxx. 1. Four crosses, 1..xxxx. 1.
1840 R. H. Barham Lay St. Dunstan in Ingoldsby Legends 1st Ser. 235
Keep clear of Broomsticks, Old Nick, and three XXX's.
1843 R. S. Surtees Handley Cross I. viii. 158
‘And you, musicians,’ turning to the promenade band, who were hard at work with some XX, ‘be getting your instruments ready.’
1856 ‘G. Eliot’ in Westm. Rev. Jan. 5
Barclay's treble X.
1886 A. G. Murdoch Sc. Readings
(ed. 2)
1st Ser. Ser. 1. 98
The XXX stout was brought in.
1826—1886(Hide quotations)
5. XYZ: used to denote some thing or person unknown or undetermined (cf. 3).
1808 S. T. Coleridge Lett. to J. P. Estlin
(1884)
105
I use it rather as an X Y Z, an unknown quantity.
1813 Ld. Byron Let. 23 Nov.
(1974)
III. 215
Junius was X. Y. Z., Esq.
a1834 S. T. Coleridge Lit. Remains
(1839)
IV. 426
[This] determines whether X Y Z be a thing or a person.
1885 J. K. Jerome On Stage ii
Among the sham agents must be classed the ‘Professors,’ or ‘X. Y. Z.'s.’
1808—1885(Hide quotations)
6. Used to represent a kiss, esp. in the subscription to a letter. O.E.D. Suppl. (1986) interpreted quot. 1763 as showing a use of this sense, but it is of a much earlier date than any other recorded use and seems more likely to show the sense ‘blessing’, perhaps with reference to the making of the sign of the cross (cf. quot. 1719 and also sense 1b; cf. also sense 10).
[1719 D. Defoe Life Robinson Crusoe 337
There was a Letter of my Partner's, congratulating me very affectionately upon my being alive,..and making two and twenty Crosses for Blessings, told me he had said so many Ave Marias to thank the Blessed Virgin that I was alive.
1763 G. White Lett.
(1901)
I. vii. 132
I am with many a xxxxxxx and many a Pater noster and Ave Maria, Gil. White.]
1878 F. Montgomery Seaforth II. iv. iv. 54
This letter..ends with the inevitable row of kisses,—sometimes expressed by × × × × ×, and sometimes by o o o o o o, according to the taste of the young scribbler.
1894 W. S. Churchill Let. 14 Mar. in R. S. Churchill Winston S. Churchill
(1967)
I. Compan. i. vii. 456
Please excuse bad writing as I am in an awful hurry. (Many kisses.) xxx WSC.
1951 S. Plath Let. 7 July
(1975)
i. 72
Some gal by the name of Sylvia Plath sure has something—but who is she anyhow?..x x Sivvy.
a1953 D. Thomas Under Milk Wood
(1954)
41
Yours for ever. Then twenty-one X's.
1982 ‘C. Fremlin’ Parasite Person vi. 40
A row of ‘X's’, hurried kisses, all he had time to scribble.
1878—1982(Hide quotations)
7. X-band: the range of microwave frequencies around 10,000 megahertz, used in radar transmission.
1946 Radar: Summary Rep. & Harp Project
(U.S. National Defense Res. Comm., Div. 14)
144/2
X-band, refers to wavelengths around 3 cm.
1952 J. F. Reintjes & G. J. Coate Princ. Radar
(ed. 3)
i. 33
Radar equipment operating..in the S, X, and K bands is called microwave radar.
1976 Sci. Amer. June 72/1
Most spacecraft now transmit to the earth a second radio signal at an X-band frequency (8·5 gigahertz).
1946—1976(Hide quotations)
8. Cinematography. X is used to denote films classified as suitable for adults only, or to which only those older than a certain age are to be admitted; so X-rated adj. (hence X-rate vb. trans.), X-rating n. Also figurative.In Britain replaced by 15 and 18 in 1983.
1950 Rep. Departm. Comm. on Children & Cinema 64 in Parl. Papers (Cmd. 7945) VII. 238
We recommend that a new category of films be established (which might be called ‘X’) from which children under 16 should be entirely excluded.
1950 Times 14 July 8/4
The X certificates..will cover films other than those of a ‘horrific’ character, which are ‘wholly adult in conception and treatment’.
1956 ‘M. Innes’ Appleby plays Chicken i. xvii. 139
‘I'm going up.’ ‘You're doing nothing of the sort. It's X Certificate stuff, my boy, and not for general exhibition. There's a high-up copper who says so.’
1958 Times 9 July 6/3
Mr. Davie..has his ‘X’ certificate pictures..in which his obsessional imagery has taken on an existence, outside the vague allusiveness of the paint, which is too specific for comfort.
1970 N.Y. Times Index 1248/2
Panel of 3 Fed judges rules Penna's new law forbidding showing of previews of x-rated movies.
1972 Daily Colonist
(Victoria, Brit. Columbia)
6 Feb. 2/3
There was only one explicit scene—the incest sequence—which caused the film to get an X (no one under 17 admitted).
1973 M. Amis Rachel Papers 136
Sebastian had gone into Oxford to see an X film (‘any X film’ he said) and to moon around looking for girls with his spotty mates.
1974 Florida FL Reporter 13 35/3
‘Community standards’ should determine whether X-rated movies should be allowed to be shown or not.
1974 Newsweek 20 May 23
His communicators..kept insisting that the transcripts actually clear the President of any crime more grievous than using X-rated language and thinking unsavory thoughts.
1976 Publishers Weekly 24 May 54/3
Most readers will surely X-rate the author's dicta; only the far-out minority will accept them.
1981 TV Picture Life Mar. 6/1
For it was daytime TV shows, or ‘soaps’ as they are affectionately called, that first explored the ‘X’-rated areas of life.
1983 Guardian 15 Oct. 10/7
In America..X-rating is used only for out-and-out porn.
1950—1983(Hide quotations)
9. X-C (or XC) skiing (North American) with pronunciation /krɒs/, cross-country skiing.
1972 J. Dean & S. Smith Wisconsin 161/1
Call it ski touring, Nordic skiing,..or simply X-C, but it all boils down to the same thing—the art of walking on skis.
1976 National Observer
(U.S.)
13 Mar. 11/1
Alpine and XC skiing.
1977 N.Y. Rev. Books 14 Apr. 42/4
(advt.)
Midwest Photographer, 33, likes bike rides, hikes, x-c skiing, concerts, theater,..seeks woman friend.
1972—1977(Hide quotations)
III. Abbreviations.
10. In writing the name Christ n. and int., esp. in abbreviated form, X or x represents the first letter /kaɪ/ of Greek ΧΡΙΤΟkhristos, and XP or xp the first two letters /kaɪrəʊ/. Hence in early times Xp̄, in modern times Xt, Xt, and X, are used as abbreviations of the syllable Christ, alone or in derivatives; thus † Xp̄en, Xp̄n = christen adj. and n., † Xp̄enned = christened adj. and n.; † Xpian, Xtian = Christian adj. and n.; Xtianity = Christianity n.; Xmas n. (Xstmas, Xtmas) = Christmas n.1 and int.†Xp̄c stands for ΧΡ contracted form of ΧΡΙΤΟ; cf. IHS.
a1100 Anglo-Saxon Chron. ann. 1021
On Xp̄es mæsse uhtan.
c1380 Eng. Wycliffite Serm. in Sel. Wks. I. 337
In þis word Vix ben but þree lettris, V, and I, and X. And V bitokeneþ fyve; I bitokeneþ Jesus; and X bitokeneþ Crist.
1426 J. Lydgate tr. G. de Guileville Pilgrimage Life Man 19951
Xp̄c þi sone, þat in þis world alighte, Vp on þe cros to suffre his passioun.
1485 Rolls of Parl. VI. 280/1
The most famous, blessed and Xpen Prince.
1485 Rolls of Parl. VI. 336/1
Any Kyng or Prynce in England Xp̄enned.
1574 J. Baret Aluearie Y Introd. sig. Lll.ijv
The long mistaking of this woorde Xp̃s, standing for Chs by abbreuation which for lacke of knowledge in the greeke they tooke for x, p, and s, and so likewise Xp̃ofer.
1598 S. Rowlands Betraying of Christ sig. Dij
Xpian the outward, inward, not at all.
1634 W. Prynne Let. in S. Gardiner Documents Proc. against W. Prynne
(1877)
33
Such right..as your Xtianity, place, and function joyntly require.
1685–6 MS. in Bk. Com. Pr. 1662
(Bodl.)
My first child..Xstened on thursday the 28 of the same month.
a1697 J. Aubrey Brief Lives: Milton
(MS. Aubrey 8. lf. 63)
He was so faire, that they called him the lady of Xts coll.
1711 T. Hearne Remarks & Coll.
(1889)
III. 155
This Note I took out of a Book of Mr. Urry of Xt. Church.
1811 P. B. Shelley Let. 17 May
(1964)
I. 90
Nor do I think her Xtianity of the most inerasible nature.
1842 G. W. Francis Dict. Arts (at cited word)
Xmas. for Christmas, Xpher. for Christopher, &c.
1845 M. Arnold Let. Mar.
(1932)
55
When Tait had well observed that strict Calvinism devoted 1000s of mankind to be eternally,—and paused—I, with, I trust the true Xtian Simplicity suggested ‘—’.
1915 A. Huxley Let. Oct.
(1969)
79
The ethics are identical with Xtian ethics.
1940 E. Pound Cantos LII–LXXI lviii. 74
They drove the Xtians out of Japan.
1966 D. Jones Let. 8–16 June in R. Hague Dai Greatcoat
(1980)
iv. 223
All chaps should be awfully good..is..more or less what the present notion of Xtianity boils down to.
a1100—1966(Hide quotations)
11.
a. Put for the initial syllable ex- of a word, or as an abbreviation for a word beginning with ex-. x's (slang): expenses. Also, in Stock Exchange quotations, xd = ex dividend, etc.
1838 H. E. Manning Let. in E. S. Purcell Life Cardinal Manning
(1896)
I. xi. 230
All the ‘Xs’, I fear,..would go out. [Note. ‘X's and Peculiars’ were the nicknames given by the Tractarians to the Evangelicals..who called themselves Christians par excellence.]
1838 H. E. Manning Let. in E. S. Purcell Life Cardinal Manning
(1896)
I. xi. 230
He writes as tenderly as if he thought you a serious ‘X’.
a1849 E. A. Poe X-ing a Paragrab in Wks.
(1856)
IV. 266
One gentleman thought the whole an X-ellent joke.
1885 Daily News 13 Mar. 2/1
New York Central Railway 925/
8 927/
8 xd.
1894 L. J. Miln Strolling Players East xv. 132
I think we might clear our X.'s... Perhaps I should explain that ‘X.'s’ means expenses.
1910 Encycl. Brit. V. 197/2
Canonists have continued to refer to the decretals of Gregory IX by the abbreviation X (Extra, i.e. extra Decretum).
1838—1910(Hide quotations)
12. Chemistry. = xenon n.
Draft additions March 2015
XL adj. extra large (esp. as a garment size).
1950 Lowell
(Mass.)
Sun 25 July 2/1
(advt.)
Nationally advertised white short sleeve sport shirts. XL size only.
2011 C. Moran How to be Woman
(2012)
vi. 111
A world where a size 12 is ‘XL’—is another piece of what strident feminists can technically dismiss as ‘total bullshit’.
1950—2011(Hide quotations)
Draft additions March 2015
XXL adj. extra extra large (esp. as a garment size).
1952 Syracuse
(N.Y.)
Herald-Jrnl. 5 Nov. 9/4
(advt.)
Tuckstich panties... Size XXL.
2001 Drapers Rec. 28 Apr. 27/3
(advt.)
T-shirts—PK polos—sweatshirt-hooded—jogpants—jogsuit. Kids and Adult S to XXL, many colours.
1952—2001(Hide quotations)
Draft additions March 2012
XRF n. X-ray fluorescence.
1954 Iron Age 15 July 110
(table)
Xrf... X-ray fluorescence.
1990 Jrnl. Petrol. 31 522
Some trace elements were..measured by XRF, in duplicate.
2007 A. M. Pollard et al. Analyt. Chem. in Archaeol. v. 119
There are a large number of examples of the use of XRF in distinguishing pottery shards from different regions.
1954—2007(Hide quotations)
Draft additions September 2008
X factor n. an indefinable but important element, esp. one that sets something or someone apart; (now) spec. star quality, special talent; cf. sense 3j.
1930 N.Y. Times 21 Jan. 24/3
We have to deal here with an unknown element in the disease. It is the same X factor which so regularly arises to sober man's pride.
1934 A. G. Melvin Building Personality viii. 70
We may know the presence of the x factor in personality if we discover phenomena which must be attributed to it.
1972 Times 14 Aug. 12/1
The ‘X’ factor that finally makes a man commit crime or become dangerously anti-social has yet to be fully explained.
1989 S. Holbeche Power Gems & Crystals ix. 132
The X-factor in sharing healing energy with another person is love and caring.
2000 F. Walker in J. Adams et al. Girls' Night In 50
The press love you. You have the X factor they can't get enough of.
2003 N.Y. Times
(National ed.)
16 Mar. ii. 20/2
Ms. Seidelman says she recognized Madonna's star quality the minute she met her. ‘She had that X factor,’ she says. ‘She had that street confidence.’
1930—2003(Hide quotations)
Draft additions June 2003
XML n. Computing Extensible Markup Language, a standard for the mark-up of electronic documents for display on the Web, which is based on SGML and allows users to customize their own tags.
1996 Series of Releases on SGML '96 in comp.text.sgml
(Usenet newsgroup)
8 Oct.
The W3C SGML Working Group will report on the status of XML, eXtensible Markup Language, on Tuesday morning. XML, which is an outgrowth of an activity of the World Wide Web Consortium, is a subset of SGML designed to be Web-friendly.
1998 New Scientist 7 Feb. 7/3
Some Web designers are already using XML to create pages, and the latest versions of Web browsers can make use of it.
2001 Computer Weekly 1 Feb. 46/5
It is being enhanced, moving away from its Wireless Markup Language (WML) roots to take advantage of XHTML, the XML-based version of the popular HTML language from which most of the Web is built.
1996—2001(Hide quotations)