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3.
the outermost part of a womans breast visible though the side of a tank top, specifically the under arm
"woah did you see the sleavage on that chick? I could almost see the whole boob"
by james prete January 04, 2008
 
1.
The exposed side view of a breast thru loose fitting clothing like sideboob
Check it out, that girls tanktop is so loose you can totally see her sleavage!
by Dash8 December 25, 2005
 
2.
The side view of a breast in loose fitting clothing, also called side boobage
hey check out that big tanktop she's wearing, you can totally see her sleavage!
by Dash8 November 08, 2005