[1] : The Collaborative International Dictionary of English v.0.48

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.
      1913 webster

   2. min. calcareous tufa.
      1913 webster
see also:
tophi toph tofus 

[2] : WordNet (r) 2.0

tophus
     n 1: a deposit of urates around a joint or in the external ear;
          diagnostic of advanced or chronic gout syn: chalkstone
     2: an incrustation that forms on the teeth and gums syn: tartar,
         calculus
     also: tophi pl
see also:
chalkstone tartar calculus tophi 

Tophus >> T Words
Tophus, definition of term: Tophus
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