Tridymite

2 definitions found

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

  Tridymite \Trid"y*mite\, n. [Gr. ? threefold. So called in
     allusion to the supposed threefold nature of the twin
     crystals.] (Min.)
     Pure silica, like quartz, but crystallizing in hexagonal
     tables. It is found in trachyte and similar rocks.
     [1913 Webster]



From WordNet (r) 2.0 [wn]:

  tridymite
       n : a mineral form of silica