Tophus \To"phus\, n.; pl. {Tophi}. [NL.: cf. F. tophus a mineral
concretion in the joint. See {Toph}.] [Written also {tofus}.]
1. (Med.) One of the mineral concretions about the joints,
and in other situations, occurring chiefly in gouty
persons. They consist usually of urate of sodium; when
occurring in the internal organs they are also composed of
phosphate of calcium.
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2. (Min.) Calcareous tufa.
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