silica

n. silicon dioxide, crystalline compound commonly found in sand and quartz (used to produce glass, cement, ceramic, and other products)

Silica redirects here. For other uses, see Silica (disambiguation) The chemical compound silicon dioxide, also known as silica or silox (from the Latin "silex"), is the oxide of silicon, chemical formula O, and has been known for its hardness since the 16th century. It is a principal component of most types of glass and substances such as concrete.Siliceous is an adjective meaning "related to silica".
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Noun
1. a white or colorless vitreous insoluble solid (SiO2); various forms occur widely in the earth's crust as quartz or cristobalite or tridymite or lechartelierite
(synonym) silicon oxide, silicon dioxide
(hypernym) oxide
(hyponym) chert
(substance-holonym) quartz

n. silica, crystalline compound commonly found in sand and quartz

(n.)
Silicon dioxide, SiO/. It constitutes ordinary quartz (also opal and tridymite), and is artifically prepared as a very fine, white, tasteless, inodorous powder.