Used as a form of burn. Originally from Ireland with the term u nasty. Now a days the pop culture uses this term to did on each others mama's. Go kill your self for disrespecting the mama's around the world.
"Yo mama so ugly, one direction went in the other direction"
"Yo mama so ugly, she looks like u. The one reading this sentence. Yeah, YOU. Thanks."
yo mama is often used for jokes to laugh at
Dude: ur fucking fat
You: yo mama fatter
Dude: *beats u up*
That's me, yo mama you've all been offending.
guy 1: yo mama so fat, when she walked past the tv I missed all 20 seasons of the Simpsons.
yo mama: hey you ugly bitch, that's me your talking about.
A reply to something stated against you, or you're bored and say it for no reason. The meaning lies in the word itself.
Yo mama fat it flattened my thighs while sitting on me. (I used it because Yo Mama is an animal)