Green’s Dictionary of Slang

(US) a close male friend .

[1902		Out West Sept. 355: And what does it appear to you, compadre? [DA]].
1976		E. Thompson Caldo Largo (1980) 53: Way it goes, compadre. Way it goes.
1987		(con. 1967) Bunch & Cole Reckoning for Kings (1989) 59: Come on, compadre. Buy you a beer.
1990		R. Doyle Snapper 62: My round, compadres, said Bertie.
2000		P. Beatty Tuff 87: I meant like ‘homey,’ ‘brother man,’ ‘compadre,’ ‘nigger’ even.