http://www.urbandictionary.com/define.php?term=boi

1. in the lesbian community, a young transgendered/androgynous/masculine person who is biologically female and presents themselves in a young, boyish way; a boidyke; often also identifies as genderqueer.

2. in the gay community, a young gay man;

3. in the BDSM community, someone who presents themselves in a young, boyish way and is usually a bottom/submissive;

A boi is a lesbian or gender-queer person who identifies most with their male energy and presents themselves as male in their appearance. They may consider themselves to be of either gender although they are anatomically female.

1) In the bdsm arena: boi means a butch who is submissive or a sexual bottom.

2) In the butch-femme arena: boi means a chronologically/behaviorally young butch.

A Butch female of the homosexual persuasion. Known to be gay or queer. Known for exceptional taste and/or style. Particularly attractive to femme lesbian women .