When a chick with big boobs is wearing a low cut shirt and a bra that is too tight, has a noticable fold in her boob in the armpit region.
The best example is the orgin of this word. At a baseball game a beer girl, who was over weight and wearing a low cut, tight tight tight shirt walked by. Her bra was so tight also that it pushed her boobs back and her boob was folded over in the armpit area. She was rocking "the origami cleavage"!!!
by Chuck Gnasty & Mr. Paule August 8, 2009