Meaning

noun a close friend who accompanies his buddies in their activities

noun bait consisting of chopped fish and fish oils that are dumped overboard to attract fish

noun a large Pacific salmon with small spots on its back; an important food fish

origin1675–85; of uncertain origin, possibly from cham, shortening of chambermate, or from comrade. Less likely from Welsh cymrawd (“fellow”), compare brawd (“brother”).

Etymology from Wiktionary, CC BY-SA 3.0