2 definitions by Morgan Freeman's evil Piñata.

... fucking seriously. Looking up Urban Dictionary, on Urban Dictionary! I- I don't even "WANT" to give you a definition of it.
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When you forget what you jam is called.
Partyguy #1: What's my jam called again. Oh yeah, Fantasy that shit's my JAM!1

Partyguy #2: You forgot your jam?

Partyguy# 1: I have jamnesia.
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