look up any word, like hipster:
 
1.
Back pain suffered by women with large breasts
Her massive fun bags were causing her horrendous rack back
by tennis ball head May 07, 2010
 
2.
When a sweaty fat fuck has folds of fat on their back that resemble saggy granny titties.
"that fat slut was walking around with her shirt wedged in her rackback.
by pete burns September 15, 2007