LGBT slang, LGBT speak, or gay slang is a set of Englishslanglexicon used predominantly among LGBT people. It has been used in various languages since the early 20th century as a means by which members of the LGBT community identify themselves and speak in code with brevity and speed to others. The acronym LGBT was popularized in the 1990s and stands for Lesbian, Gay, Bisexual, and Transgender.
During the first seven decades of the 20th century, a specific form of Polari was developed by gay men and lesbians in urban centres of the United Kingdom within established LGBT communities. Although there are differences, contemporary British gay slang has adopted many Polari words. The 1964 legislative report Homosexuality and Citizenship in Florida contains an extensive appendix documenting and defining the homosexual slang in the United States at that time.SCRUFF launched a gay-slang dictionary app in 2014, which includes commonly used slang in the United States from the gay community. Specialized dictionaries that record LGBT slang have been found to revolve heavily around sexual matters.
Slang is ephemeral. Terms used in one generation may pass out of usage in another. For example, in the 1960s and 1970s, the terms "cottage" (chiefly British) and "tearoom" (chiefly American) were used to denote public toilets used for sex. By 1999, this terminology had fallen out of use to the point of being greatly unrecognizable by members of the LGBT community at large.
Many terms that originated as gay slang have become part of the popular lexicon. For example, the word drag was popularized by Hubert Selby Jr. in his book Last Exit to Brooklyn. Drag has been traced back by the Oxford English Dictionary (OED) to the late 19th Century. Conversely, words such as "banjee", while well-established in a subset of gay society, have never made the transition to popular use. Conversations between gay men have been found to use more slang and fewer commonly known terms about sexual behavior than conversations between straight men.
In the Philippines, many LGBT people speak with Swardspeak, or "gay lingo", which is a more extensive use of slang as a form of dialect or way of speaking. Other argots are spoken in southern Africa (Gayle language and IsiNgqumo) and Indonesia (Bahasa Binan). More specifically, in a country like Thailand, LGBT slang was always present in their history due to their religious, behavioral, and social nature. Though, before the term LGBT was introduced, the Thai community would use the terms Kathoey and Tom. The term Kathoey was used to describe transgender women who dress, act, or partake in surgery to become female, and the term Tom as well as "handsome girls" in Thai was used to describe women who liked women. Homosexuality and transgenderism has always existed throughout their history, as well as their behavioral nature did not align with heterosexual ideals. 
General slang terms
100-footer – an obviously gay or lesbian person (as if visible from 100 feet away) (US)
Horatian – from the belated nineteenth century, term utilized at Oxford amongst Lord Byron along with his compatriots to a bisexual individual; a bisexual+ masculine person (UK)
Molly/Tommy – In 18th century England, the term "molly" was used for male homosexuals, implying effeminacy; "tommy", a slang term for a homosexual woman in use by 1781, and may have been coined by analogy. See Molly house.
outsider – being “neither/nor” when it comes to normative taboos and self-centered communities
platinum star gay – gay men who were born by a C-section procedure (US)
queer – originally a slur against homosexuals, transgender people, and anyone who does not fit society's standards of gender and sexuality; recently reclaimed and used as umbrella term for sexual and gender minorities
sapphic or WLW (woman-loving-woman) – synonymous with lesbian, but used nowadays to encompass attractions and relationships between women, regardless of their sexual or romantic orientation, sometimes including non-binary gynephiles
unicorn – a bisexual, usually female, who desires multiple partners and is willing to join an existing married couple and sexually satisfy both members of the couple. So-named because bisexuals willing to enter to such an arrangement are considered rare or non-existent, while couples seeking such a partner ("unicorn hunters") are common.
Terms describing androgynous or intersex people
futanari (ふたなり, "to be of two kinds", seldom: 二形, 双形, lit. "dual form") – Japanese word for hermaphroditism, which is also used in a broader sense for androgyny.: 79, 81 The term is also heavily associated with a genre of hentai defined by sexualization of characters simultaneously possesssing breasts, a penis and vagina.
hermie – an androgynous or intersex person, often considered a slur.
altersex – a term describing an alternative sex in fiction or a body plan that is usually inaccessible in real life.
Terms describing transgender and non-binary people
boymoder – a transgender woman who socially presents in a masculine gender role, typically in places where transgender individuals are discriminated against, or due to not being out as transgender.
cuntboy / dickgirl – a female-to-male (FtM) and male-to-female (MtF) transgender/transsexual person, respectively, who has not had genital surgery, sometimes used for fictional characters
egg – a transgender person who has not yet realized they are trans; used by transgender people when aspects of one's personality or behavior remind them of gender-related aspects of themselves before they realized they were trans
trap — slur for someone whose perceived gender is opposite their anatomical sex, particularly a trans woman or effeminate boy. Implies that others who are attracted to them (typically heterosexual men) are maliciously deceived (i.e. "trapped") regarding their "real" gender. Considered derogatory and dehumanizing.
Terms related to transgender and non-binary people
chaser / tranny chaser – someone attracted to transgender people. Often used in a pejorative fashion, chasers to value them for their trans status alone, rather than being attracted to them as a person
clock – to recognize someone as transgender.
deadname – as a noun, a transgender person's birth name. As a verb, to refer to someone by their deadname.
girldick – a transfeminine person's penis, especially one changed by hormone use. Also known as girlcock or gock.
malefail – typically of transmasculine people, to be gendered as feminine when trying to present in a masculine gender role.
packing – the act of wearing padding or a phallic object to present the appearance of a penis
girlfag – a cisgender woman who identifies as a heterosexual woman except in the context of her attraction to gay/bisexual men; in these instances, she regards herself as a gay man too.
guydyke or lesboy – a cisgender man who identifies as a heterosexual man except in the context of his attraction to lesbian/bisexual women; in these instances, he regards himself as a lesbian too.
The following slang terms have been used to represent various types of people within the LGBT community:
bear – a larger and often hairier man who projects an image of rugged masculinity. The bear subgroup is among the oldest and largest of the LGBT community. Pride.com says "Bears are on the heavier side, either muscular, beefy, or chunky. They wouldn't dream of shaving their body hair (which comes in abundance) and they usually have a full beard to match. They exude masculinity, and are some of the kindest men you'll meet in your entire life."Attitude magazine says bears are "typically older" with a big build, a belly, and lots of hair. There are many bear subtypes, including the black bear (Black or African American men), the brown bear (Hispanic men), the grizzly bear ("dominant bears of extreme stature or hairiness"), the koala bear (Australian men), the panda bear (men of Asian descent), and the polar bear, which represents an older bear with white hair.
cub – a younger bear. Pride.com describes cubs as "baby bears" or "large, hairy guys in their teens and 20's who are on their way to becoming a bear".
wolf – Pride.com says, "Similar to an otter, a wolf has some hair and is in between a twink and a bear. However, there are some key differences between wolves and otters. Wolves typically have a lean, muscular build and are sexually aggressive."Attitude says wolves are "typically older and masculine" with a "muscular/athletic build".
bull – Pride.com says a bull is a "hunky, muscular" bodybuilder who weighs 200 pounds or more. The website says, "These men are big, strong and have muscles you didn't even know existed."Attitude says bulls have a "super-muscular build" with any hair style, and can be any age.
chicken – a young twink.Attitude says chickens are "hairless and young" with a slim or skinny build.
chickenhawk – a typically older man who seeks younger men. From chickenhawk, a designation for several birds which are thought to hunt chickens.
pig – someone who is "more focused on sex than anything else, often into kinkier and somewhat seedier sexual practices", according to Pride.com.
pup / puppy – in animal roleplay, someone who wants to be treated like a puppy, "with love and affection", by a handler.Attitude says pups are "young and submissive" with a slender build and little hair.
^"swish definition, meaning". dictionary.cambridge.org. Cambridge Dictionaries Online. Retrieved 20 February 2015. swish noun [C] (LIKE A WOMAN) › US slang disapproving a man who behaves or appears in a way that is generally considered more suited to a woman, and who does not have traditional male qualities
^"swish - Gay Slang Dictionary". Archived from the original on 2 April 2015. Retrieved 28 February 2015. swish #n. To overplay or over do homosexual gestures; the traits of an effeminate male homosexual. Source: [1930's] #Passive homosexual. #To walk speak or move in the manner of an weak effeminate boy or man; the stereotype effeminate homosexual.
^Edward Anthony Gibbons (2008). A Cultural Affair. iUniverse. p. 6. ISBN9780595611614. On many, a cold freezing night, of temperatures hovering near zero, the finocchios tease and try to encourage Tedesco to join in their warm body orgies.
^Bergman, S. Bear; Barker, Meg-John (2017). "Non-binary Activism". In Richards, Christina; Bouman, Walter Pierre; Barker, Meg-John (eds.). Genderqueer and Non-Binary Genders. Critical and Applied Approaches in Sexuality, Gender and Identity. Palgrave Macmillan. p. 43. ISBN978-1-137-51052-5.
^Chasin, C. J. DeLuzio (2015). "Making Sense in and of the Asexual Community: Navigating Relationships and Identities in a Context of Resistance". Journal of Community & Applied Social Psychology. 25 (2): 167–180. doi:10.1002/casp.2203.
^"The 'A' in LGBT". Counterpoint. 35 (1): 8. September 2013.