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1.
a breast that sags and hides in a woman's armpit when she is laying horozontal.
I thought she had nice tits until she took off her bra and layed down. Armtits, dude.
by 9Boomer July 26, 2006
 
2.
Where a woman is so fat her tits bulge out of her armpit area causing arm tits
Hey dude where does that fat bitches armpits end and tits start, those are some mean armtits
by Co6 November 01, 2013
 
3.
the fat that squeezes out of a strapless top where the chest meets the armpit.
that chick should never wear a tube top- her armtits are too big!
by miss speller January 24, 2014