the quality or state of intense emotional and usually erotic attraction of a woman to another woman.

As it was first used in the late 16th century, the word lesbian was the capitalized adjectival term referring to the Greek island of Lesbos. Its connotation of “female homosexuality” was added in the late 19th century, when an association was made with the tender and often passionate poetry written by Lesbian poet Sappho (c. 610–c. 580 BC) to and about other women in her female coterie. The history of lesbianism to the present has been largely reconstructed by late 20th-century European and American theorists; perceptions from other cultures are not readily available.

Just as heterosexual orientation produces a great variety of behaviours, so, too, lesbianism presents no unified face. Some lesbians hide or deny their orientation, marrying in order to be accepted by their families and communities. Others—often in the relative anonymity of an urban setting—prefer to live openly as lesbians, sometimes bearing and rearing children.

Broadly speaking, in Europe and North America, many of the issues faced by lesbians at the turn of the 21st century were not radically different from those that concerned either heterosexual women or many gay men. Like heterosexual women, lesbians are affected by such issues as equal pay or the historical exclusion of women from medical research studies, the latter of which has led to a lack of understanding about the effect of lesbian sexuality on women's health. Like many gay men, many lesbians in long-term relationships regret the lack of legal recognition for same-sex unions. Other issues of concern to lesbians include child rearing (ranging from the inability to adopt a partner's offspring to laws barring same-sex adoption), the sharing of medical health benefits with a partner, the right to make health decisions for a partner, taxes, inheritance, and so on.