Tuber (?), n.[L., a hump. knob; probably akin to tumere to swell. Cf. Tumid.] 1. (Bot.) (a) A fleshy, rounded stem or root, usually containing starchy matter, as the potato or arrowroot; a thickened root-stock. See Illust. of Tuberous. (b) A genus of fungi. See Truffle.
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2. (Anat.) A tuberosity; a tubercle.
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