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(n)
Synonyms: silica
silicon dioxide
silicon oxide
Hyponyms: chert
flint
silex
Hypernyms: oxide
SubstanceMeronyms: cristobalite
crystal
lechatelierite
quartz
quartz glass
tridymite
vitreous silica