abbr. : shorthand or umbrella term for sexuality, gender identity. It refers to anyone who is non-heterosexual or non-cisgender.
The initials stand for; Lesbian, Gay, Bisexual, Transgender, Questioning, Queer, Intersex, Agender, Asexual. The “+” symbol simply stands for all of the other sexualities and genders that aren’t included in these few letters.