a word used as a comeback when you have no other comeback to use: a word used to get someone to leave you alone

another term for "your mom"
"Hey what are you eating?"
"ur mum."
by olafsfluffyD October 16, 2015
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The insult of all insults. When you're stuck and have nothing to say, just say 'ur mum'.
"This pizza is still warm"
"Ur mum's pussy is still warm...hurhurhurhur".
by p00_p00 August 30, 2006
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wen ur frin bein a cheky cunt n da call of duds u jus sey ur mum
"fukin cheky cunt ur mum is hairy"
by YOOOOOOOOOOOO March 31, 2015
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The apparent zenith of comebacks, used almost exclusively by 12-16 year olds.
Person 1: You sir, are a veritable nincompoop.
Person 2: ERR UR MUM LOL!1!

'I AD SEX WIV UR MUM LOL'
by Dougal September 27, 2004
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the british form of "ur mom", a overused comeback that is funny if used as a joke or your kidding when u say it.
Person:Fuck U!
British Person: I fucked ur mum!

b_i_t_c_h678: i have sooo much homework.
this1person923: ur mom has so much homework! OH! BURN! WAT NOW!?!?!?!
b_i_t_c_h678: wtf lol
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"ur mum" is not ur actualy ur mum but a person that represents ur mum
it is used when you are really stoned or dont hav a good enough come back
Jon: what does my cooking taste like?
Michael: ur mum
by Germans December 11, 2006
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