X

• POS: Noun, Verb (transitive)

CIDE DICTIONARY

X,  

 X, the twenty-fourth letter of the English alphabet, has three sounds; a compound nonvocal sound (that of ks), as in wax; a compound vocal sound (that of gz), as in example; and, at the beginning of a word, a simple vocal sound (that of z), as in xanthic. See Guide to Pronunciation, 1913 Webster]
" The form and value of X are from the Latin X, which is from the Greek ks, though in the one now in common use it represents an aspirated sound of k."  [1913 Webster]

OXFORD DICTIONARY

X, n. (also x) (pl. Xs or X's)
1 the twenty-fourth letter of the alphabet.
2 (as a Roman numeral) ten.
3 (usu. x) Algebra the first unknown quantity.
4 Geom. the first coordinate.
5 an unknown or unspecified number or person etc.
6 a cross-shaped symbol esp. used to indicate position (X marks the spot) or incorrectness or to symbolize a kiss or a vote, or as the signature of a person who cannot write.

X, symb. (of films) classified as suitable for adults only.

Usage

Formerly used in the UK to indicate that persons under 18 would not be admitted; it was replaced in 1983 by 18, but is still used in the US.

DEVIL DICTIONARY

X

in our alphabet being a needless letter has an added invincibility to the attacks of the spelling reformers, and like them, will doubtless last as long as the language. X is the sacred symbol of ten dollars, and in such words as Xmas, Xn, etc., stands for Christ, not, as is popular supposed, because it represents a cross, but because the corresponding letter in the Greek alphabet is the initial of his name -- _Xristos_. If it represented a cross it would stand for St. Andrew, who "testified" upon one of that shape. In the algebra of psychology x stands for Woman's mind. Words beginning with X are Grecian and will not be defined in this standard English dictionary.

THESAURUS

X

Calvary cross, Christogram, Decalogue, Greek cross, Jerusalem cross, John Hancock, Latin cross, Maltese cross, Russian cross, T, Ten Commandments, ankh, autograph, avellan cross, chi, chi-rho, christcross, cipher, countermark, countersign, countersignature, counterstamp, crisscross, cross, cross ancre, cross botonee, cross bourdonee, cross fitche, cross fleury, cross formee, cross fourchee, cross grignolee, cross moline, cross of Cleves, cross of Lorraine, cross patee, cross recercelee, cross-crosslet, crossbones, crosslet, crucifix, cruciform, crux, crux ansata, crux capitata, crux decussata, crux gammata, crux immissa, crux ordinaria, dagger, decade, decagon, decagram, decahedron, decaliter, decameter, decare, decastere, decastyle, decasyllable, decemvir, decemvirate, decennary, decennium, decigram, deciliter, decimeter, decurion, device, endorsement, ex, exing, fork cross, gammadion, hand, initials, inverted cross, long cross, mark, mark of signature, monogram, papal cross, pectoral cross, potent cross, rood, saltire, seal, sigil, sign manual, signature, signet, subscription, swastika, tau, ten, tenner, trefled cross, visa, vise, voided cross

ROGET THESAURUS

X

Ignorance

N ignorance, nescience, tabula rasa, crass ignorance, ignorance crasse, unfamiliarity, unacquaintance, unconsciousness, darkness, blindness, incomprehension, inexperience, simplicity, unknown quantities, x, y, z, sealed book, terra incognita, virgin soil, unexplored ground, dark ages, smattering, sciolism, glimmering, dilettantism, bewilderment, incapacity, pedantry, charlatanry, charlatism, Philister, Philistine, ignorant, nescient, unknowing, unaware, unacquainted, unapprised, unapprized, unwitting, unweeting, unconscious, witless, weetless, a stranger to, unconversant, uninformed, uncultivated, unversed, uninstructed, untaught, uninitiated, untutored, unschooled, misguided, unenlightened, Philistine, behind the age, shallow, superficial, green, rude, empty, half-learned, illiterate, unread, uninformed, uneducated, unlearned, unlettered, unbookish, empty-headed, dizzy, wooly-headed, pedantic, in the dark, benighted, belated, blinded, blindfolded, hoodwinked, misinformed, au bout de son latin, at the end of his tether, at fault, at sea, caught tripping, unknown, unapprehended, unexplained, unascertained, uninvestigated, unexplored, unheard of, not perceived, concealed, novel, ignorantly, unawares, for anything, for aught one knows, not that one knows, Int, God knows, Heaven knows, the Lord knows, who knows, nobody knows, ignorance never settles a question, quantum animis erroris inest!, small Latin and less Greek, that unlettered small-knowing soul, there is no darkness but ignorance.