Etimología y Historia de bull-dyke

también bulldyke, bull-dike, "lesbiana con tendencias masculinas," 1926; anteriormente bulldyker, bulldycker se usaba para lo mismo, para 1906, donde se decía que era jerga de Filadelfia.

Según el "Dictionary of American Slang," una fuente de 1896 lista dyke como jerga para "la vulva," y Farmer y Henley ("Slang and Its Analogues," 1893) tiene "hedge on the dyke" para "el vello púbico femenino." 

[T]he word appears first in the long forms, bulldiker and bulldyking, both used in the 1920s by American blacks. No African antecedents have been found for the term, however, which leads to the possibility that this is basically just another backcountry, barnyard word, perhaps a combination of BULL and DICK. [Rawson]

También existe la variante bulldagger (1932) que el OED considera ser la palabra principal aunque la ortografía bulldyker está atestiguada antes.