cock (n.1)youdaoicibaDictYouDict[cock 词源字典]
"male chicken," Old English cocc "male bird," Old French coc (12c., Modern French coq), Old Norse kokkr, all of echoic origin. Old English cocc was a nickname for "one who strutted like a cock," thus a common term in the Middle Ages for a pert boy, used of scullions, apprentices, servants, etc.

A common personal name till c. 1500, it was affixed to Christian names as a pet diminutive, as in Wilcox, Hitchcock, etc. Slang sense of "penis" is attested since 1610s (but compare pillicock "penis," from c. 1300); cock-teaser is from 1891. A cocker spaniel (1823) was trained to start woodcocks. Cock-and-bull is first recorded 1620s, perhaps an allusion to Aesop's fables, with their incredible talking animals, or to a particular story, now forgotten. French has parallel expression coq-à-l'âne.[cock etymology, cock origin, 英语词源]
tease (n.)youdaoicibaDictYouDict
1690s, "act of teasing," from tease (v.). Meaning "one who teases" is from 1852. Specifically as short for cock-teaser, it was in use by 1976.