1 definition by JannetTheBeast!

A nickname describing a midget with an extremely large penis.
Girl 1: Hey you know peter?
Girl 2: Which one? The midget?
Girl 1: Yeah.
Girl 2: What about him?
Girl 1: He's a mastadon.
Girl 2: No Way!
by JannetTheBeast! May 30, 2008
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