The Collaborative International Dictionary of English v.0.48:
Cock \Cock\ (k[o^]k), n. [AS. coc; of unknown origin, perh. in
imitation of the cry of the cock. Cf. Chicken.]
1. The male of birds, particularly of gallinaceous or
2. A vane in the shape of a cock; a weathercock.
Drenched our steeples, drowned the cocks! --Shak.
3. A chief man; a leader or master. [Humorous]
Sir Andrew is the cock of the club, since he left
4. The crow of a cock, esp. the first crow in the morning;
He begins at curfew, and walks till the first cock.
5. A faucet or valve.
Note: Jonsons says, "The handle probably had a cock on the
top; things that were contrived to turn seem anciently
to have had that form, whatever was the reason."
Skinner says, because it used to be constructed in
forma crit[ae] galli, i.e., in the form of a cock's
6. The style of gnomon of a dial. --Chambers.
7. The indicator of a balance. --Johnson.
8. The bridge piece which affords a bearing for the pivot of
a balance in a clock or watch. --Knight.
9. a penis. [vulgar]
Ball cock. See under Ball.
Chaparral cock. See under Chaparral.
Cock and bull story, an extravagant, boastful story; a
Cock of the plains (Zool.) See Sage cock.
Cock of the rock (Zool.), a South American bird (Rupicola
aurantia) having a beautiful crest.
Cock of the walk, a chief or master; the hero of the hour;
one who has overcrowed, or got the better of, rivals or
Cock of the woods. See Capercailzie.