See chum in Webster's New World Roget's A-Z Thesaurus II
noun
A person whom one knows well, likes, and trusts:
amigo, brother, confidant, confidante, familiar, friend, intimate1, mate, pal. (Informal) bud2, buddy. (Slang) sidekick. See loveOne who shares interests or activities with another:
associate, companion, comrade, crony, fellow, mate. (Informal) buddy, pal. See near
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