Gay is an adjective meaning "carefree", "happy", or "bright and showy"; however in modern usage, gay is a word usually used, as either a noun or adjective, to refer to homosexuals; persons sexually oriented toward members of their own gender.
"Gay", when used as an adjective, sometimes describes traits associated with both homosexual men and women, their culture, or perceived lifestyle. The term lesbian, on the other hand, is used exclusively in a gender-specific way to describe homosexual women.
Encyclopedia & Dictionary Resources
Gay, Lesbian, and Bisexual Studies :: Social Sciences
History :: Gay, Lesbian, and Bisexual

Gay Male and Lesbian Sexuality and Related Issues - An annotated bibliography presenting a cross section of available resources on gay and lesbian sexuality and related issues.
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Gay Slang Dictionary - Text format dictionary of terms commonly heard in the gay community.
Meta Description: [ dictionary of slang terms in gay life ]
gaydemographics.org - Features census and official figures about same-sex couples. Includes the United States and other nations.
Meta Description: [ Utah: Tabulation of the 2000 Census data in regard to same-sex couples in Utah, broken down into several geographical categories. ]
Hugh Young's Lexicon of Polari - Includes glossary with alternative spellings, word origins, and pronunciation.
Outcyclopedia - Reference and resource guide for the gay, lesbian, bisexual, and transgendered communities. Alphabetical listings with related resources. Accepts contributors.
Meta Description: [ Outcyclopedia - online queer, lesbian, gay, bisexual, and transgendered encyclopedia ]
Polari - British Gay Slang - A introduction to Polari, the archaic British gay slang, with a wordlist, related links, and bibliography.
QueerAmerica - National database of queer resources with standard and advanced search options.
Meta Description: [ QueerAmerica - The national database of gay, lesbian, bisexual and transgender resources ]
The Gay and Black Glossary - Definitions of terms used in personal ads and other slang. Includes related links and a chart showing numerical probability of HIV infection for various sexual activities.
Meta Description: [ Gay and Black Glossary of slang terms. ]