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1.
cycling for a cause. ie, riding bike across America for a charity
i mamoo, do you?
by ratatatt July 07, 2011
 
2.
mamoo is a nickname for your favorite pet. Its slag for "my moo", not that a cow is the pet in question, but slang nonetheless. It can also be baby talk.
hello mamoo! ur my baby!
by jweno January 03, 2005