Spelled various ways, yass queen or yaass queen or yas kween, it was originally a phrase among a type of urban
black American women said seriously or ironically, then moved to populations imitating them, and onto becoming a meme because of it. Now the phrase has morphed into a noun and verb to connote the type of people use the phrase, i.e., over-the-top or extra, people
particularly vociferous in their political and social views, the overly
opinionated, people deemed loud and obnoxious, etc.