When a female has a flat ass that looks like it is just part of her legs. Because the ass looks like part of the legs the ass looks like it goes all the way down to the ankles. An ass to ankles ass can be big or small. Not to be confused with negative ass.
"Hey man, whats with her ass, it's all flat." "Yeah, she has ass to ankles"
by Copernicus P. Einstein March 11, 2009
a very crowded situation (e.g. four people in the back seat of a sedan, the taste of chicago on the 4th of July, etc)
Okay, we are just about ass to ankles back here, Maeby. Do you want to hop on your cousin’s lap there, please?
by Dr Tobias Funke December 13, 2009