Green’s Dictionary of Slang

(gay) to enter the homosexual world, to ‘come out’.

1964		‘R. Blake’ Amer. Dict. Sexual Terms [Simes:DLSS].
1975		‘N. Jennings’ Chicken Lickin’ 22: Every kid ought to debut as part of a threesome [Simes:DLSS].
1985		H.P. Jeffers Portrait in Murder 170: ‘He started as a teenage hustler, correct?’ ‘Yes, he debuted with Donny Wills’ [Simes:DLSS].