Meaning

noun a female homosexual

noun a resident of Lesbos

adjective of or relating to or characterized by homosexual relations between woman

originFrom Latin Lesbiana, from Ancient Greek Λέσβος (Lésbos) + Latin adjective suffix -iana; by reference to Sappho of Lesbos (whence also sapphist, sapphic), known for her sentimental poems about women. This sense of the word may have been borrowed from, or influenced by, the German cognate lesbisch, where it is found in medical literature from the 1830s.

Etymology from Wiktionary, CC BY-SA 3.0