silica Meaning, Definition & Usage

  1. noun a white or colorless vitreous insoluble solid (SiO2); various forms occur widely in the earth's crust as quartz or cristobalite or tridymite or lechatelierite
    silicon oxide; silicon dioxide.

WordNet

Sil"i*ca noun
Etymology
NL., from L. silex, silics, a flint.
Definitions
  1. (Chem.) Silicon dioxide, SiO. It constitutes ordinary quartz (also opal and tridymite), and is artifically prepared as a very fine, white, tasteless, inodorous powder.

Webster 1913