Ur mom is a phrase used to be funny or comical, people often use it when being sarcastic.
guy 1: wow bro! Ur mom is a milf !
guy 2: no, ur mom is.
someone I had sex with last nigh
dave: where were you last night
me: I was with ur mom *wink wink nudge nudge*
A word that a person named Sydney would use
Person 1 how u doin
Sydney ur mom
This word is meant to offend people that don't have moms and kids that are orphans!
Ur mom was so stunned she left the hospital as soon as she saw you!