A person who actively seeks to speak or write in favour of a cause, particularly regarding marginalised groups. In Queer contexts, a person who actively seeks to end inequality of LGBTQIA+ people and causes, e.g. an advocate for same-sex marriage; a transgender rights advocate.

A cisgender/straight (non-Queer) person who supports the LGBTQIA+ community.

A heterosexual and/or cisgender ally to the Queer community.

Now typically used to describe somebody who is both heterosexual and cisgender (cishet) but supportive of the Queer community; an individual who does not identify as Queer/LGBTQIAP+ but recognises and works towards fixing the discrimination, health issues and acceptance of Queer/LGBTQIAP+ peoples.