Boi (plural: bois) is a term used within LGBT and butch and femme communities to refer to a person's sexual and gender identity. In lesbian communities, there is an increasing acceptance of variant gender expression, as well as allowing people to self-identify with labels such as boi. The term may denote a number of possibilities that are not mutually exclusive:

Boi may also refer to a female-assigned at birth or female-bodied person, sometimes transsexual, transgendered, or intersexed, sometimes not—that generally does not identify as, or only partially identifies as feminine, female, a girl, or a woman. Some "bois" identify as one or more of these, but they almost always identify as lesbians, dykes, or queers. Many are also genderqueer or practice genderfuck. Bois may prefer a range of pronouns, including "he", "she", or non-binary and gender-neutral pronouns such as "they", "co", "hir", "sie", "zie", and "ey". The term has found increasing usage in the larger LGBT culture.

Boi or BOI may refer to:

Sexual slang is a set of linguistic terms and phrases used to refer to sexual organs, processes, and activities; they are generally considered colloquial rather than formal or medical, and some may be seen as impolite or improper.

Related to sexual slang is slang related to defecation and flatulence (toilet humor, scatolinguistics). References to the anal tract are often given a sexual connotation in the context of anal sex (in particular, in a context of male homosexuality).

While popular usage is incredibly versatile in coining ever new short-lived synonyms, old terms with originally no pejorative colouring may come to be considered inappropriate over time. Thus, terms like arse/ass, cunt, cock and fuck should not be considered "slang," since they are the inherited common English terms for their referents, but they are often considered vulgarisms and are replaced by euphemisms or scientific terminology in "polite" language.

Terms of disparagement are used to refer to members of a given sexual minority, gender, sex, or sexual orientation in a derogatory or pejorative manner. They are used as insults by persons who are not or do not wish to be associated with the group being disparaged. For example, queer can be used as an insult by those seeking to deprecate homosexual, bisexual, and transsexual people, but the word has also undergone reclaiming, such that it can be used positively within that community. Which terms are used as slurs is determined by a society's or subculture's set of values, especially its biases against genders (sexism). For example, words such as whore and slut are typically used to refer to sexually promiscuous women.