Just about. The greatest comeback to anything. Used mainly when talking about the size of genitals, but can apply to anything else.
Person A - Hey look at our science. That's bigger than yours!
Person B - That's not what your mom said last night!
Person C - Oh BURN.
Person B - That's not what your mom said last night!
Person C - Oh BURN.
by More Awesome Than Thou November 13, 2005
Get the That's not what your mom said last nightmug. A comeback that people say when someone says, " I bet you are terrible at sex." Or other comebacks. Then that person would come back and say, " That's not what your Mom said in bed last night."
Guy #1: Your dick is probably the size of half of a raisin.
Guy#2: That's not what your Mom said in bed last night.
Guy#2: That's not what your Mom said in bed last night.
by jazmine1 April 19, 2018
Get the That's Not What Your Mom Said in Bed Last Nightmug.