What is Mom Joke?
1.
A lame joke, pun, or play on words that your mom would say, such as "have a nice trip, see you next fall". Does not have to be told by your mom, just has to be lame.
"Hey Trevor, have a nice trip, see you next fall! Haha!"
"Dude, that was fucking lame."
"Yeah man, that was a total mom joke."
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2.
A mom joke is when someone makes a joke and laughs really hard at it but no one else does. It's pretty much PAST the "fake laugh joke" point.
Bob: Hey hey what did the kids say to the rabbi? Silly rabb-
Joe: Say another fucking mom joke and I'm gonna slit your throat.
See