Definition: Nowadays, the adjective "gay" refers to a man's particular sex orientation. Previously, it meant "happy" and "carefree" in another languages but this use is not usual nowadays.
Sometimes, the term gay also refers to the homosexual community culture, like "gay history", or another aspects perceived by other, as "gay music". The word gay is used to refer to the homosexual relationship between two men, like in "gay marriage". This usage is far more popular than the suggested term "LGBT". Its main reasons is that "gay" excludes bisexuals and transsexuals.
While gay is used in some environments to refer to all homosexual persons, the term "lesbians" refers only to homosexual women. In many cases, "gay" is only used in reference to men.
