LGBTQ (also commonly seen as LGBT, LGBT+, LGBTQ+, and LGBTQIA+) is an initialism for lesbian, gay, bisexual, transgender and queer or questioning. It is an umbrella term, broadly referring to all sexualities, romantic orientations, and gender identities which are not heterosexual, heteroromantic, cisgender, or endosex.

In the 1990s, gay, lesbian, and bisexual activists adopted the term LGB, supplanting narrower terms such as "gay or lesbian". Terminology eventually shifted to LGBT, as transgender people became more accepted within the movement. Around that time, some activists began to reclaim the term queer, seeing it as a more radical and inclusive umbrella term, though others reject it, due to its history as a pejorative. In recognition of this, the 2010s saw the adoption of LGBTQ, and other more inclusive variants.

Some versions of the term, such as LGBT+ and LGBTQ+ add a plus sign, to represent additional identities not captured within the acronym. Many further variants exist which add additional identities, such as LGBTQIA+ (for intersex, asexual, aromantic, and agender) and 2SLGBTQ+ (for two-spirit), LGBTQQ (for queer and questioning), or which order the letters differently, as in GLBT and GLBTQ.

The collective of all LGBTQ people is often called the LGBTQ community. These labels are not universally agreed upon by everyone that they are intended to include. For example, some intersex people prefer to be included in this grouping, while others do not. Various alternative umbrella terms exist across various cultures, including queer; same gender loving (SGL); and Gender, Sexual and Romantic Minorities (GSRM).

The first widely used term, homosexual, now a term used primarily in scientific contexts, has at times carried negative connotations in the United States. Gay became a popular term in the 1970s.

As lesbians forged more public identities, the phrase gay and lesbian became more common. A dispute as to whether the primary focus of their political aims should be feminism or gay rights led to the dissolution of some lesbian organizations, including Daughters of Bilitis, which was founded by Del Martin and Phyllis Lyon, but disbanded in 1970 following disputes over which goal should take precedence. As equality was a priority for lesbian feminists, disparity of roles between men and women or butch and femme were viewed as patriarchal. Lesbian feminists eschewed gender role play that had been pervasive in bars as well as the perceived chauvinism of gay men; many lesbian feminists refused to work with gay men or take up their causes.

Lesbians who held the essentialist view that they had been born homosexual and used the descriptor lesbian to define sexual attraction often considered the separatist opinions of lesbian-feminists to be detrimental to the cause of gay rights. Bisexual and transgender people also sought recognition as legitimate categories within the larger minority community.

In the late 1970s and the early 1980s, after the elation of change following group action in the 1969 Stonewall riots in New York City, some gays and lesbians became less accepting of bisexual or transgender people. Critics said that transgender people were acting out stereotypes, and bisexuals were simply gay men or lesbian women who were afraid to come out and be honest about their identity. Each community has struggled to develop its own identity including whether, and how, to align with other gender and sexuality-based communities, at times excluding other subgroups; these conflicts continue to this day. LGBTQ activists and artists have created posters to raise consciousness about the issue since the movement began.

From about 1988, activists began to use the initialism LGBT in the United States. Not until the 1990s within the movement did gay, lesbian, bisexual, and transgender people gain equal respect. This spurred some organizations to adopt new names, as the GLBT Historical Society did in 1999. Although the LGBT community has seen much controversy regarding universal acceptance of different member groups (bisexual and transgender individuals, in particular, have sometimes been marginalized by the larger LGBT community), the term LGBT has been a positive symbol of inclusion.

Beginning in the 1990s, the term queer was beginning to be adopted by the community to support gay-pride and reclaim the term from its earlier pejorative use as scholars have shown. The field of study of the LGBTQ community is called queer studies, in recognition of this reclamation and used as an umbrella term for the wider community as the academic response to the Stonewall riots. The acronym LGBT eventually evolved to LGBTQ in recognition of the community's reclamation of the term.

In 2016, GLAAD's Media Reference Guide states that LGBTQ is the preferred initialism, being more inclusive of younger members of the communities who embrace queer as a self-descriptor. Some people consider queer to be a derogatory term originating in hate speech and reject it, especially among older members of the community.

Many variants of the term LGBT exist, such as the more inclusive LGBT+ and variations that change the order of the letters or include additional letters. At least some of the components of sexuality (regarding hetero, bi, straight), and also gender are stated to be on different spectrums of sexuality. Other common variants also exist, such as LGBTQIA, with the I standing for intersex and the A standing for asexual, aromantic, or agender, and LGBTQIA+, where "the '+' represents those who are part of the community, but for whom LGBTQ does not accurately capture or reflect their identity". Longer initialisms have been criticized as confusing or unwieldy, sometimes being referred to as "alphabet soup", and mocked with labels such as LGBTQWERTY, LGBTQXYZ, and alphabet mafia. The implication that the initialism refers to a single community is also controversial.

Although identical in meaning, LGBT may have a more feminist connotation than GLBT as it places the "L" (for "lesbian") first. LGBT may also include additional Qs for "queer" or "questioning" (sometimes abbreviated with a question mark and sometimes used to mean anybody not literally L, G, B or T) producing the variants LGBTQ and LGBTQQ. The order of the letters has not been standardized; in addition to the variations between the positions of the initial "L" or "G", the mentioned, less common letters, if used, may appear in almost any order. In Hebrew and Peninsular Spanish, LGTB (להט"ב) is used, that is, reversing the letters "B" and "T". Variant terms do not typically represent political differences within the community, but arise simply from the preferences of individuals and groups.

The terms pansexual, omnisexual, fluid and queer-identified are regarded as falling under the umbrella term bisexual (and therefore are considered a part of the bisexual community). Some use LGBT+ to mean "LGBT and related communities". Other variants may have a "U" for "unsure"; a "C" for "curious"; another "T" for "transvestite"; a "TS", "2S", or "2" for "two-spirit" persons; or an "SA" for "straight allies". The inclusion of straight allies in the LGBT initialism has proven controversial, as many straight allies have been accused of using LGBT advocacy to gain popularity and status in recent years, and various LGBT activists have criticised the heteronormative worldview of certain straight allies. Some may also add a "P" for "polyamorous" or "pangender", an "H" for "HIV-affected", or an "O" for "other". The initialism LGBTIH has seen use in India to encompass the hijra third gender identity and the related subculture.

Adding the term allies to the initialism has sparked controversy, with some seeing the inclusion of ally in place of asexual/aromantic/agender as a form of LGBT erasure. There is also the acronym QUILTBAG (queer and questioning, unsure, intersex, lesbian, transgender and two-spirit, bisexual, asexual and aromantic, and gay and genderqueer). Similarly LGBTIQA+ stands for "lesbian, gay, bisexual, transgender, intersex, queer/questioning, asexual and many other terms (such as non-binary and pansexual)".

In Canada, the community is sometimes identified as LGBTQ2 (lesbian, gay, bisexual, transgender, queer and two spirit). Depending on which organization is using the abbreviation, the choice of initialism changes. Businesses and the CBC often simply employ LGBT as a proxy for any longer abbreviation, private activist groups often employ LGBTQ+, whereas public health providers favour the more inclusive LGBT2Q+ to accommodate twin spirited indigenous peoples. For a time, the Pride Toronto organization used the much lengthier initialism LGBTTIQQ2SA, but appears to have dropped this in favour of simpler wording. Prime Minister Justin Trudeau was also criticized for using the 2SLGBTQQIA+ initialism. As of July 2023, the Government of Canada's official term is 2SLGBTQI+. Trudeau's new acronym was criticized by some social media users.

The term trans* has been adopted by some groups as a more inclusive alternative to "transgender", where trans (without the asterisk) has been used to describe trans men and trans women, while trans* covers all non-cisgender (genderqueer) identities, including transgender, transsexual, transvestite, genderqueer, genderfluid, non-binary, genderfuck, genderless, agender, non-gendered, third gender, two-spirit, bigender, and trans man and trans woman. Likewise, the term transsexual commonly falls under the umbrella term transgender, but some transsexual people object to this.

Those who add intersex people to LGBT groups or organizations may use the extended initialism LGBTI, or LGBTIQ.

The relationship of intersex to lesbian, gay, bisexual and trans, and queer communities is complex, but intersex people are often added to the LGBT category to create an LGBTI community. Some intersex people prefer the initialism LGBTI, while others would rather that they not be included as part of the term. Emi Koyama describes how inclusion of intersex in LGBTI can fail to address intersex-specific human rights issues, including creating false impressions "that intersex people's rights are protected" by laws protecting LGBT people, and failing to acknowledge that many intersex people are not LGBT. Organisation Intersex International Australia states that some intersex individuals are same-sex attracted, and some are heterosexual, but "LGBTI activism has fought for the rights of people who fall outside of expected binary sex and gender norms". Julius Kaggwa of SIPD Uganda has written that, while the gay community "offers us a place of relative safety, it is also oblivious to our specific needs".

Numerous studies have shown higher rates of same-sex attraction in intersex people, with a recent Australian study of people born with atypical sex characteristics finding that 52% of respondents were non-heterosexual; thus, research on intersex subjects has been used to explore means of preventing homosexuality. As an experience of being born with sex characteristics that do not fit social norms, intersex can be distinguished from transgender, while some intersex people are both intersex and transgender.

In the early 2010s, asexuality and aromanticism started gaining wider recognition. Around 2015, they were included in the expanded initialism LGBTQIA, with the A standing for asexual, aromantic, commonly grouped together as a-spec along with agender.

Asexual individuals experience minimal to no sexual attraction to others; asexuality may be considered a sexual orientation or a lack of a sexual orientation. Aromantic individuals lack romantic attraction to others, yet they can still forge profound emotional connections and strong bonds with people without the romantic component. Agender individuals either have no gender identity or possess a neutral or genderless gender identity.

Some people have mistakenly claimed the A stands for ally, but allies are not a marginalized group and mentions of A for ally have regularly sparked controversy as a form of LGBT erasure.

The initialisms LGBT or GLBT are not agreed to by everyone that they encompass. For example, some argue that transgender and transsexual causes are not the same as that of lesbian, gay, and bisexual (LGB) people. This argument centers on the idea that being transgender or transsexual has to do more with gender identity, or a person's understanding of being or not being a man or a woman irrespective of their sexual orientation. LGB issues can be seen as a matter of sexual orientation or attraction. These distinctions have been made in the context of political action in which LGB goals, such as same-sex marriage legislation and human rights work (which may not include transgender and intersex people), may be perceived to differ from transgender and transsexual goals.

A belief in "lesbian and gay separatism" (not to be confused with the related "lesbian separatism") holds that lesbians and gay men form (or should form) a community distinct and separate from other groups normally included in the LGBTQ sphere. While not always appearing in sufficient numbers or organization to be called a movement, separatists are a significant, vocal, and active element within many parts of the LGBT community. In some cases separatists will deny the existence or right to equality of bisexual orientations and of transsexuality, sometimes leading to public biphobia and transphobia. In contrasts to separatists, Peter Tatchell of the LGBT human rights group OutRage! argues that to separate the transgender movement from the LGB would be "political madness", stating that:

Queers are, like transgender people, gender deviant. We don't conform to traditional heterosexist assumptions of male and female behaviour, in that we have sexual and emotional relationships with the same sex. We should celebrate our discordance with mainstream straight norms.

The portrayal of an all-encompassing "LGBT community" or "LGB community" is also disliked by some lesbian, gay, bisexual, and transgender people. Some do not subscribe to or approve of the political and social solidarity, and visibility and human rights campaigning that normally goes with it, including LGBT pride marches and events. Some of them believe that grouping together people with non-heterosexual orientations perpetuates the myth that being gay/lesbian/bi/asexual/pansexual/etc. makes a person deficiently different from other people. These people are often less visible compared to more mainstream gay or LGBT activists. Since this faction is difficult to distinguish from the heterosexual majority, it is common for people to assume all LGBT people support LGBT liberation and the visibility of LGBT people in society, including the right to live one's life differently from the majority. In the 1996 book Anti-Gay, a collection of essays edited by Mark Simpson, the concept of a 'one-size-fits-all' identity based on LGBT stereotypes is criticized for suppressing the individuality of LGBT people.

Writing in the BBC News Magazine in 2014, Julie Bindel questions whether the various gender groupings now, "bracketed together[,] ... share the same issues, values and goals?" Bindel refers to a number of possible new initialisms for differing combinations and concludes that it may be time for the alliances to either be reformed or go their "separate ways". In 2015, the slogan "Drop the T" was coined to encourage LGBT organizations to stop support of transgender people as they say that sexual orientation, LGB, does not share similarity with gender identity, the T. The campaign has been condemned by many LGBT groups as transphobic.

Many have expressed desire for an umbrella term to replace existing initialisms. Queer gained popularity as an umbrella-term for sexual and gender minorities in the 21st century. The term remains controversial, particularly among older LGBT people, who perceive it as offensive due to its historical usage as a slur, as well as those who wish to dissociate themselves from queer radicalism, and those who see it as amorphous and trendy. Some younger people feel queer is a more politically charged, more powerful term than LGBT. In a 2018 U.S. study, about 1 in 5 LGBTQ people identified as "queer".

SGM, or GSM, an abbreviation for sexual and gender minorities, has gained particular currency in government, academia, and medicine. GSRM is also used to include romantic minorities such as aromanticism.

In New Zealand, New Zealand Human Rights Commission uses "Rights of Sexual and Gender Minorities" to discuss LGBT rights.

In India, the Constitutional Bench of the Supreme Court of India, when decriminalizing homosexuality in the case of Navtej Singh Johar v. Union of India (2018), said:

Individuals belonging to sexual and gender minorities experience discrimination, stigmatization, and, in some cases, denial of care on account of their sexual orientation and gender identity. However, it is important to note that 'sexual and gender minorities' do not constitute a homogenous group, and experiences of social exclusion, marginalization, and discrimination, as well as specific health needs, vary considerably. Nevertheless, these individuals are united by one factor - that their exclusion, discrimination and marginalization is rooted in societal heteronormativity and society's pervasive bias towards gender binary and opposite-gender relationships, which marginalizes and excludes all non-heteronormative sexual and gender identities.

In the US, the term "Sexual and Gender Minority" has been adopted by the National Institutes of Health, the Centers for Medicare & Medicaid Services and the UCLA Williams Institute, which studies SGM law and policy. Duke University and the University of California San Francisco both have prominent sexual and gender minority health programs. An NIH paper recommends the term SGM because it is inclusive of "those who may not self-identify as LGBT ... or those who have a specific medical condition affecting reproductive development". A publication from the White House Office of Management and Budget states, "We believe that SGM is more inclusive, because it includes persons not specifically referenced by the identities listed in LGBT."

A UK government paper favors SGM because initials like LGBTIQ+ stand for terms that, especially outside the Global North, are "not necessarily inclusive of local understandings and terms used to describe sexual and gender minorities". An example of usage outside the Global North is the Constitution of Nepal, which identifies "gender and sexual minorities" as a protected class.

In Canada especially, the term 2SLGBTQ+ is seen, with the first two characters standing for two-spirit; the whole term stands for two-spirit, lesbian, gay, bisexual, trans, queer and questioning, and is intended as a term encompassing all sexual- and gender-minorities. For some indigenous people, two-spirit invokes a combination of identities, including sexual, gender, cultural, and spiritual.

Some people advocate the term "minority sexual and gender identities" (MSGI, coined in 2000) for the purpose of explicitly including all people who are not cisgender and heterosexual or "gender, sexual, and romantic minorities" (GSRM), which is more explicitly inclusive of minority romantic orientations, but those have not been widely adopted either. Other rare umbrella terms are Gender and Sexual Diversities (GSD), MOGII (Marginalized Orientations, Gender Identities, and Intersex) and MOGAI (Marginalized Orientations, Gender Alignments and Intersex).

SGL (same gender loving) is sometimes favored among gay male African Americans as a way of distinguishing themselves from what they regard as white-dominated LGBT communities.

In public health settings, MSM ("men who have sex with men") is clinically used to describe men who have sex with other men without referring to their sexual orientation, with WSW ("women who have sex with women") also used as an analogous term.

MVPFAFF is an abbreviation for Māhū, Vakasalewa, Palopa, Fa'afafine, Akava'ine, Fakaleitī (Leiti), and Fakafifine. This term was developed by Phylesha Brown-Acton in 2010 at the Asia Pacific Games Human Rights Conference. This refers to those in the rainbow Pacific Islander community, who may or may not identify with the LGBT initialism.

• LGBT music
• Androphilia and gynephilia
• Gender and sexual diversity
• LGBT symbols
• Takatāpui – the Māori language equivalent of LGBT

• Archives of glbtq.com, the GLBTQ encyclopedia
• Directory of U.S. and international LGBT Community Centers (archived 10 October 2008)
• American Psychological Association's Lesbian, Gay, Bisexual and Transgender Concerns Office