Found 2 items, similar to tridymite.
English → English (WordNet) Definition: tridymite tridymite n : a mineral form of silica
English → English (gcide) Definition: Tridymite 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]