Green’s Dictionary of Slang

1. an exceptionally virile man; thus cocksmanship, a display of such virility.

c.1930		(ref. to late 19C) N. Kimball Amer. Madam (1981) 104: They were pretty good cocksmen, but very sentimental.
c.1935		[title] ‘Tijuana Bible’: The Love Guide. Approved by the Cocksman Union.
1956		A. Ginsberg ‘Howl’ Howl and Other Poems 12: N.C., secret hero of these poems , cocksman, and Adonis of Denver.
1968		G. Cuomo Among Thieves 241: All this screw them, fuck them routine, and what kind of cocksmen they were.
1974		(con. 1940s) E. Thompson Tattoo (1977) 201: Chuck was a cocksman. If she knew Chuck, she wasn’t a cherry.
1980		M. Thelwell Harder They Come 245: ‘Baba’ talking as usual about him is a cocksman.
1990		R. Campbell Sweet La-La Land (1999) 172: Here’s the barmaid prancing around with a string up her crack and her treasures hanging out for all to see. Must have been a terrible temptation for a cocksman like Younger.
1999		J. Ridley Everybody Smokes in Hell 129: Her trick tore himself away from his underwhelming cocksmanship.
1999		‘Master Pimp’ Pimp’s Rap 198: His body was drenched with sweat. He was stroking with the craftsmanship of a professional cocksman.
2005		Roger’s Profanisaurus in Viz Apr. 47: cuntsmann. A cocksman, stickman. A Don Juan type, highly skilled in the pursuit of poontang.
2010		L. Berney Gutshot Straight [ebook] ‘Mr. Ted Boxman?’ ‘Like “Cocksman,”’ Gina explained, but with a B instead of a C’.

2. (US black) a male prostitute.

1994

C. Major Juba to Jive.