a third party referance to a snap (come back) or somthing bad that had happened.
person1: lol look at that chick she's so fat!
Person2: Your MOMS fat...
Person3: OH SNAP!
Person1: FUCK *walks away in shame*
person1: Man, my mom just caught me smokin Jib
, so i sicked a wogehkak
on her ass.
Person2: OH SNAP!