Green’s Dictionary of Slang

(orig. US) a masculine lesbian.

1906		J. Richardson Parke Human Sexuality 309: In American homosexual argot, female inverts, or lesbian lovers, are known euphemistically as ‘bulldykers,’ whatever that may mean: at least that is their sobriquet in the ‘Red Light’ district of Philadelphia.
1926		Van Vechten Nigger Heaven 12: ‘Atlantic City Joe’s?’ ‘Too many pink-chasers an’ bulldikers.’ ‘Where den?’.
1932		‘R. Scully’ Scarlet Pansy 147: There were bulldikers with their sweeties.
1935		A.J. Pollock Und. Speaks 15/1: Bull dyker, a female sexual prevert; lewd act.
1939		H. Miller Tropic of Capricorn (1964) 226: One of the German relatives had just arrived [...] a maiden aunt who looked like a bull-dyker.
1940		S.J. Perelman letter 10 Apr. in Crowther Don’t Tread on Me (1987) 28: A group of spectacular bull-dikers of the Elsa Maxwell set.
1946		Drake & Cayton Black Metropolis 573: A damn bull-diker who’s been messing with women here.
1950		Goldin et al. DAUL 36/1: Bull-dyker. A lesbian.
1965		K. Worthy Homosexual Generation Ch. xvi: A bulldiker: Usually heavy-set, very masculine, Butch haircut, no make-up. Does not like children. Always plays the part of the male in the sex act.
1966		Trimble 5000 Adult Sex Words and Phrases 32: bull-dicker (Vulg.) n. A Bulldagger; a female Homosexual.
1971		R.D. Pharr S.R.O. (1998) 233: ‘Those bulldikers called me everything [...] for wanting to kick a cripple out’.
1972		(con. 1950s) D. Goines Whoreson 83: First of all your main lady is a bull-dyker.
1980		E. Folb Runnin’ Down Some Lines 160: See them real masculine women. Righteous bulldikers. I don’ fool roun’ wid ’em.
1982		Maledicta VI:1+2 (Summer/Winter) 127: I mean ‘a female homosexual who plays the masculine rôle’ [...] a stinkfinger bull-diker.
1987		R. Campbell Alice in La-La Land (1999) 189: How come you’re walking around looking like a faggot? Hey, you’re not a bull dyker, are you?