Female homosexuality, or lesbianism, derives its name from the island of Lesbos in the eastern Aegean. Here the female poet, Sappho, composed passionate love poems addressed to young women in the 7th century BC. Unfortunately only one of her completed odes survives, and in another of these she mentions her daughter, so 'lesbianism' did not exclude marriage and childbirth. Indeed, she is supposed to have committed suicide by jumping off a cliff after falling in love with a boatman called Pharon.

As the examples above indicate, the Ancient Greeks do not seem to have defined themselves as exclusively homosexual or heterosexual, which raises some difficulties when trying to compare their activities with modern notions of sexuality.

Plato's Symposium is perhaps the most famous text on this subject. In it the playwright Aristophanes speculates that there were once three sexes - male, female and hermaphrodite, each of which had four legs, arms and other organs. Zeus punished these original humans for fighting against him and sliced them in half, which is the reason there are three kinds of persons - heterosexuals, and female and male homosexuals - each of us is always looking for our 'other half'. Humor aside, the Symposium also contains a lengthy discussion of the nature of physical desire and spiritual love, which has become known as 'Platonic love'. Plato's suggestion is that this form of love is far superior because it is not tied to the body's drives.