person 1: dude i just got a win on fortnite
person 2: dude i just got ur mom
person 1: im fat
person 2: ur mom is fat
person 1: shut up
person 2: ur mom shut up
person 2: dude i just got ur mom
person 1: im fat
person 2: ur mom is fat
person 1: shut up
person 2: ur mom shut up
by rosii-ivii October 20, 2019

by KatakuriFan69 September 20, 2022

is commonly used as a comeback and jokes. It means exactly what it sounds like, but please do not use this one when talking to a sibling it is not the same and ruins it.
person 1: what were you doing today?
person 2: ur mom
sibling 1: what were you doing today?
sibling 2: ur mom
sibling 1:... we have the same mom...
sibling 2: yeah sorry
person 2: ur mom
sibling 1: what were you doing today?
sibling 2: ur mom
sibling 1:... we have the same mom...
sibling 2: yeah sorry
by _N.e.x_ March 7, 2022

Ur Mom is a heavenly body which has mass more than a black hole and somehow doesn't collapse in on herself. Ur Mom measures about 69 lightyears in diameter and consumes anything she comes in contact with.
Person A: Did you know that Jupiter's diameter is more than 100,000 km?
Person B: Not nearly as big as Ur Mom.
Person B: Not nearly as big as Ur Mom.
by websurferoftheages March 24, 2022
