cross (n.) Look up cross at Dictionary.com
Old English cros (mid-10c.), from Old Irish cros, probably via Scandinavian, from Latin crux (accusative crucem, genitive crucis) "stake, cross" on which criminals were impaled or hanged, hence, figuratively, "torture, trouble, misery;" originally a tall, round pole; possibly of Phoenician origin. Replaced Old English rood. Also from Latin crux are Italian croce, French croix, Spanish and Portuguese cruz, Dutch kruis, German Kreuz.
cross (adj.) Look up cross at Dictionary.com
"ill-tempered," 1630s, probably from 16c. sense of "contrary, athwart," especially with reference to winds and sailing ships, from cross (n.). Cross-purposes "contradictory intentions" is from 1660s.
cross (v.) Look up cross at Dictionary.com
c.1200, "make the sign of a cross," from cross (n.). Sense of "to go across" is from c.1400; that of "to cancel by drawing lines over" is from mid-15c. Related: Crossed; crossing.