The word lesbian is derived from the name of the Greek island of Lesbos, home to the 6th-century BCE poet Sappho. From various ancient writings, historians gathered that a group of young women were left in Sappho's charge for their instruction or cultural edification.Little of Sappho's poetry survives, but her remaining poetry reflects the topics she wrote about: women's daily lives, their relationships, and rituals. She focused on the beauty of women and proclaimed her love for girls. Before the mid-19th century, the word lesbian referred to any derivative or aspect of Lesbos, including a type of wine.
In Algernon Charles Swinburne's 1866 poem Sapphics, the term lesbian appears twice but capitalized both times after twice mentioning the island of Lesbos, and so could be construed to mean 'from the island of Lesbos'. In 1875, George Saintsbury, in writing about Baudelaire's poetry, refers to his "Lesbian studies" in which he includes his poem about "the passion of Delphine" which is a poem simply about love between two women which does not mention the island of Lesbos, though the other poem alluded to, entitled "Lesbos", does.Use of the word lesbianism to describe erotic relationships between women had been documented in 1870. In 1890, the term lesbian was used in a medical dictionary as an adjective to describe tribadism (as "lesbian love"). The terms lesbian, invert and homosexual were interchangeable with sapphist and sapphism around the turn of the 20th century. The use of lesbian in medical literature became prominent; by 1925, the word was recorded as a noun to mean the female equivalent of a sodomite.