twoback

A "twoback" is a woman with no visibly protruding breasts. See also: "flat as a board."

Lucy the twoback rarely goes on second dates.

"Is that a stop sign or a twoback?"

by snowshoesny September 27, 2009

Twobacker

A girl whose breats are very small. The overall appearance is one of a person who posses two backs on the upper torso.

Hey check that chick out over there she is stunning, shame she is a twobacker.

Hey dude I felt like a necrophiliac when I was doing Sarah last night she was all ribs, a real twobacker

by Mp900rr July 18, 2009