X, is the 22d letter of our alphabet; and a double consonant. It was not used by the Hebrews or ancient Greeks; for as it is a compound letter, the ancients, who used great simplicity in their writings, expressed this letter by its component letters c, s. Neither have the Italians this letter, but express it by f. X begins no word in our language but such as are of Greek origin; and is in few others but what are of Latin derivation; as perplex, reflexion, diffusion, &c. We often express this sound by single letters, as ch, in backs, necks; by ks, in booke, bookes; by ct, in access, accidents; by ct, in action, ambition, &c. The English and French pronounce it like cr or ks; the Spaniards like c before o, viz. Alexandro, as if it were Alexander. In numerals it is prefixed to 10, whence in old Roman manuscripts it is used for denarius; and as such seems to be made of two V's placed one over the other. When a dash is added over it, thus X, it signifies 10,000.

in botany; a genus of plants of the clas monosperma, order pentandra, and arranged in the natural classification under the 49th order, compositae. The male flowers are composite, common calyx imbricated; corollae mono-petalous, tubular, quinquefied. Female: calyx involucrum of two leaves, containing two flowers; corolla o; drupa, dry, prickly; nucleus bilocular. There are five species; only Xanthoxylum, one of which is a native of Britain, the flurnarium or leafy burdock. The stem of this plant is a foot and a half high, thick, often spotted; leaves heart-shaped, lobed; on long footstalks. Flowers, male and female, many together, in the axil of the leaves. The leaves are bitter and astringent. A decoction of the whole plant affords a showy yellow colour, but it is better if only the flowers are used. Horses and goats eat it; cows, sheep, and swine refuse it.