A Fat Trap is when
you're on a social networking website, and see a good looking profile picture. Upon going
profile picture, you see other photos of the person, and realize
they are incredibly fat, and are actually ugly.
1: Dude, check out this
hot chick's profile
2: That is definitely a fat trap dude, look at her other picturesPerson
1: *checks pictures* oh god...thanks man, you saved me.