colloq. [f. CHUM + -Y1.] Intimate, sociable.

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1884.  G. H. Boughton, in Harper’s Mag., Sept., 536/2. I … saw them form into small chummy groups.

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1888.  Illust. Lond. News, Xmas No. 7/1. Be as chummy with him as you can.

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