LGBT, or GLBT, is an initialism that stands for lesbian, gay, bisexual, and transgender. In use since the 1990s, the term is an adaptation of the initialism LGB, which was used to replace the term gay in reference to the LGBT community beginning in the mid-to-late 1980s. Activists believed that the term gay community did not accurately represent all those to whom it referred.

The initialism has become adopted into the mainstream as an umbrella term for use when labeling topics pertaining to sexuality and gender identity. For example, the LGBT Movement Advancement Project termed community centres, which have services specific to those member of the LGBT community, as "LGBT community centers", in a comprehensive studies of such centres around the United States.