silicon

UK: /ˈsɪlɪkən/ US: /ˈsɪlɪkən, -ˌkɑn/ ,(sil′i kən, -kon′)

WordReference Random House Learner's Dictionary of American English © 2025

sil•i•con /ˈsɪlɪkən, -ˌkɑn/   n. [uncountable]

1. Chemistry a nonmetallic element, occurring in minerals and rocks and making up more than one fourth of the earth's crust: used in steelmaking, computer chips, etc.

WordReference Random House Unabridged Dictionary of American English © 2025

sil•i•con  (sil′i kən, -kon′), n. [Chem.]

1. Chemistry a nonmetallic element, having amorphous and crystalline forms, occurring in a combined state in minerals and rocks and constituting more than one fourth of the earth's crust: used in steelmaking, alloys, etc. Symbol: Si;
   at. wt.: 28.086;
   at. no.: 14;
   sp. gr.: 2.4 at 20°C.

• silic(a) + -on, as in carbon and boron 1817

Collins Concise English Dictionary © HarperCollins Publishers::

silicon / ˈsɪlɪkən/ noun

1. a brittle metalloid element that exists in two allotropic forms; occurs principally in sand, quartz, granite, feldspar, and clay. It is usually a grey crystalline solid but is also found as a brown amorphous powder. It is used in transistors, rectifiers, solar cells, and alloys. Its compounds are widely used in glass manufacture, the building industry, and in the form of silicones. Symbol: Si; atomic no: 14; atomic wt: 28.0855; valency: 4; relative density: 2.33; melting pt: 1414°C; boiling pt: 3267°C
2. (modifier; sometimes capital) denoting an area of a country that contains a density of high-technology industry

Etymology: 19th Century: from silica, on the model of boron, carbon