look up any word, like doxx:
 
2.
a phrase to follow any word or sentence whether it makes sense or makes u look like a fuckin tool, said whenever someone speaks to you or anyone within hearing distance.
"hey man u comin to the shops"
"thats what ur mum said"
"mate, ur a fuckin tool"
by thats sum funny shit September 11, 2003

Words related to thats what your mum said

wyms acronym comeback insult mum
 
1.
To piss someone off, royally.
"Ow, i'm in pain"
"That's what your mum said."
by -Ben- March 14, 2005