Cut off moan
A moan by a female in which they will moan often to the point the moan is cut off by another moan.
Brad: You see that one porno with that chick?
Chad: Yea she had a cut off moan.
Chad: Yea she had a cut off moan.
Moan-off
A fight between 2 people where they have to moan better and louder than the other person!
Dude 1: YO DUDE! I AND KATE HAD A MOAN-OFF
Dude 2: WOW! LET'S HAVE IT!
Dude 1 and 2 both moan
Dude 2: WOW! LET'S HAVE IT!
Dude 1 and 2 both moan