arched back 

When a female arches her lower back. Usually done in a standing position, bending her knees slightly, sticking her butt out, and forming her lower back into an arch for an erotic pose to get a males attention. (i.e a cat arching its back)

Damn Jillian can really arch her back!!

The cat arched its back.

Arched Back is the hottest pose a girl can do.

arched back by Sugadaddy897 March 18, 2009

arched all the way back 

What a girl does show off her butt if she has one, and be or try to be sexy. Typically girls with no ass do this as well to have some butt

Jessica has a flat ass so she arched all the way back when she saw hot guys.

arched all the way back by wowcanunot March 9, 2014

Back Archer 

When you have to push a fart out so hard, you involuntarily arch your back.

I really had to work hard to squeeze that fart out, it was a back archer!

Back Archer by Johnny Voodoo June 27, 2009