Tribadism
In the eighteenth century, the definition of a 'tribade' overlapped with that of a female hermaphrodite. 8 "What matters most about the concept of lesbians as hermaphrodites, is not its accuracy, but its function: this theory served the interests of those who wanted to frighten women into heterosexual passivity. By cutting off lesbians from their own female-ness, writers could reduce them to exceptional (and therefore, harmless) freaks of nature." 9 Society found these types of women to be deviants, and therefore, tribadism was often referred to as being the "silent sin". 10 In addition to female hermaphrodites, women with close female friends, spinsters, as well as women with masculine traits, were often labeled as being tribades.
Although male homosexuality received more attention than female homosexuality, women were not supposed to admit any sort of knowledge of the word lesbianism, or its implications, for fear that they would then also be labeled as being tribades. Because of the silent treatment towards lesbianism, no laws were made in which acts of a lesbian nature could be punished. For, to create laws, was to admit the existence of lesbianism.
Male authority figures wanted to believe that lesbianism did not exist. "Most people of the time were ignorant of the existence of the phenomenon of tribady. No lesbian networks or subculture existed. Tribady was far less known than sodomy; and the taboo on it was at least as great. Practically no woman did know any examples of sexual relations between women and few, at any rate of the common people, had even heard of them... Therefore, it is logical that those women would think: if I covet a woman, I must be a man." 11 This, however, is obviously not the case considering the previously mentioned materials, coupled with the fact that a large of the women were illiterate, and therefore unable to record their own experiences.
(from Sex in Georgian England, by A.D. Harvey)