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1. underboob
October 17, 2009 Urban Word of the Day
cleavage visible from the part of the shirt that covers the bottom of the female breasts
If that is not a deliberate underboob, I don't know what is.
2. underboob
Hands down, one of the finest aspects of a woman's anatomy that can be enjoyed in any public venue.

Underboob is achieved by wearing a very short halter top or cropped tank, also known as an underboob shirt, which exposes the bottom areas of a woman's breasts.

Much like the combination of low-rise jeans and a thong, the underboob shirt can only successfully be worn by select few women.
In an ideal situation, a hottie will wear an underboob shirt to accessorize her low-rise jeans/thong combination. When this happens, all men in the vicinity will regard her as "hot" or "a sexy bitch", while their wives/girlfriend may refer to her as "trashy" or "a slutty bitch", but that's okay. Everyone knows she's a sexy bitch and they all want to do her.
by X. Phoratus Feb 21, 2005 add a video
3. underboob
Underboob: The only time in life when gravity is your friend.
"She's got underboob, so there's a small chance her boobs will slip out of her top, thanks to our good friend GRAVITY"
4. underboob
better than cleavage.
I love underboob.
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