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1 definition by Grace is gone

A wingman for all men, a guy's guy. He walks up to a group of girls and engages each of them in short conversation, thus throwing the chum in the water. He leaves the group and each of the girls are now interested in meeting a guy due to the chummer's charm. His friends follow and chat up these girls that are ready to bite: hook, line and sinker.
He went fishing for his friends, he's a chummer.
by Grace is gone May 01, 2010