I coined the term in my 1992 Fantagraphics comic of the same name. So back off slang stealers. It is named for an ass tampon made of toilet paper which looks like a biscuit when molded by the butt. It is not a name for a turd.
Synonyms for butt biscuit
On this page, you will find 30 slang terms related to butt biscuit. Some of the top words include: butt biscuit, Arse Biscuit, Teep, shit ticket, mergleh, and 25 more.