This phrase is used (mostly in England) as one of the best way to end a conversation. The reason for this is because there is no way to reply to it.
Example 1:
Joe: What do you want for dinner tonight?
Jeff: Ur mum
Example 2:
Bob: Harry you’re so ugly
Harry: Ur mum
Example 3:
Teacher: Harvey, did you do your homework?
Harvey: No
Teacher: Why not?
Harvey: Ur mum
Joe: What do you want for dinner tonight?
Jeff: Ur mum
Example 2:
Bob: Harry you’re so ugly
Harry: Ur mum
Example 3:
Teacher: Harvey, did you do your homework?
Harvey: No
Teacher: Why not?
Harvey: Ur mum
by Ur mum definition February 18, 2022
Get the ur mummug. Robbie’s mum is a junkie reprobate that cuts about behind the nisa locals and the jet garages all over Scotland. She loves selling her body for pills and syringes, Robbie’s gran is also Swiss cheese.
by Cumbum12 April 18, 2023
Get the Robbie’s Mummug. Janette is a typical Horse Mum. I heard her tell her daughter the other day
Leah go stand in front of sparky If some stones get thrown by that mower we can't have them hit him. He's my favourite horse
Leah go stand in front of sparky If some stones get thrown by that mower we can't have them hit him. He's my favourite horse
by Groundhogg June 28, 2017
Get the Horse Mummug. by Arkadiakruu December 18, 2018
Get the Your mummug. by hewpro October 4, 2021
Get the euans mummug. 
