D defs.my
Entry 1 sense Webster, 1913

Silica

/sĭl'-ək-ə/ · Sil·i·ca · IPA /ˈsɪl.ɪ.kə/
01 n. Silicon dioxide, SiO�. It constitutes ordinary quartz (also opal and tridymite), and is artifically prepared as a very fine, white, tastele…
  1. 1.
    Silicon dioxide, SiO�. It constitutes ordinary quartz (also opal and tridymite), and is artifically prepared as a very fine, white, tasteless, inodorous powder.(Chem.)