Cross

A cross is a geometrical figure consisting of two intersecting lines or bars, usually perpendicular to each other. The lines usually run vertically and horizontally. A cross of oblique lines, in the shape of the Latin letter X, is also termed a saltire in heraldic terminology.

The word is recorded in 10th-century Old English as cros, exclusively for the instrument of Christ's crucifixion, replacing the native Old English word rood. The word's history is complicated, it appears to have entered English from Old Irish, possibly via Old Norse, ultimately from the Latin (or its accusative crucem and its genitive crucis), "stake, cross". The English verb to cross arises from the noun c. 1200, first in the sense "to make the sign of the cross"; the generic meaning "to intersect" develops in the 15th century. The Latin word was, however, influenced by popular etymology by a native Germanic word reconstructed as*krukjo (English , Old English crycce, Old Norse krokr, Old High German krucka). This word, by conflation with Latin crux, gave rise to Old French crocier (modern French crosse), the term for a shepherd's crook, adopted in English as crosier.

Latin crux referred to the gibbet where criminals were executed, a stake or pole, but not necessarily to intersecting or "cruciform" beams. The Latin word derived from the verb crucio "to torture" (c.f. English ). Latin crux originally referred to the tree or stake on which criminals were crucified in the pre-imperial period. This was later specified as crux acuta or crux simplex. The method of execution may have been adopted from the Phoenicians. The addition of a transverse bar, to which the criminal would be fastened with nails or cords, dates to a later period. The Latin name of the diagonal cross is crux decussata (as it were " cross", after the Roman numeral); the heraldic term saltire (meaning "stirrup") is introduced only towards the end of the medieval period.

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