It is a phrase in similar form to Go Fuck Yourself or Suck Your Nan. It can also be used in a more literal sense if your Mum is an actual SCHLAAAAGGG!!!!
"Hey shopkeeper, have you got twenty Bensons"
"No"
"Oh Dick on your Mum"
"What did you say?"
"Fucking double Dick on your Mum"
"You shouldn't say that!!"
"African Elephant Dick on your Mum!!!!
"No"
"Oh Dick on your Mum"
"What did you say?"
"Fucking double Dick on your Mum"
"You shouldn't say that!!"
"African Elephant Dick on your Mum!!!!
by YaNansPumsDead March 31, 2013
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