the animal world equivalent of an "oops baby"; a mating between two dogs that is not intended, usually between two very different dog breeds producing ugly puppies
Example 1:
Dammit Jim, I told you to keep your beagle from jumping the fence into my backyard and trying to get friendly with my Pekingese---I don't need any Peagle puppies, those things are ugly!

Example 2:

Girl 1: What kind of dog is that?
Girl 2: It's my Pom-A-Pug!
Girl 1: A what now?
Girl 1: A designer breed mix of a pomeranian and a pug
Dude 1: Looks like a backyard mistake to me!
Girl 1: *crying*
by voiceofcollege May 15, 2010
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