The stomach a future mom gets when she's pregnant. Usually used when trying to decide if a woman is pregnant or not.
1. James: Hey Bill, Did You See Cathy?

Bill: Yeah She Got Big Didn't She?

James: Naw I Think That's A Mummy Tummy

2. "Excuse me, are you fat or is that just a mummy tummy?"
by The Groove DJ February 28, 2011
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