silicon

American  

[sil-i-kuhn, -kon] / ˈsɪl ɪ kən, -ˌkɒn /

noun

Chemistry.

1. 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. Si; 28.086; 14; 2.4 at 20°C.

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silicon British  

/ ˈsɪlɪkən /

noun

1. 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

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silicon Scientific  

/ sĭl′ĭ-kŏn′ /

1. A metalloid element that occurs in both gray crystalline and brown noncrystalline forms. It is the second most abundant element in the Earth's crust and can be found only in silica and silicates. Silicon is used in glass, semiconductors, concrete, and ceramics. Atomic number 14; atomic weight 28.086; melting point 1,410°C; boiling point 2,355°C; specific gravity 2.33; valence 4.

2. See Periodic Table

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silicon Cultural  

1. A chemical element from which semiconductors are made. It is also used in the manufacture of glass, concrete, brick, and pottery.

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Etymology

Origin of silicon

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

Compare meaning

How does silicon compare to similar and commonly confused words? Explore the most common comparisons:

• silica vs. silicon

Example Sentences

Bringing silicon photonics technology in-house will improve supply chain and cost structure, one analyst said.

From The Wall Street Journal • Apr. 15, 2026

DustPhotonics develops silicon photonics photonic integrated circuits, or SiPho PICs, which are chips that integrate optical components including lasers and detectors to move data using light.

From MarketWatch • Apr. 14, 2026

Conventional computers use electricity within silicon chips to make calculations.

From BBC • Apr. 13, 2026

“We believe we have a clear path to sustained long-term growth as our installed base expands across AI, silicon photonics, power semiconductors, and other high-performance applications,” Erickson said Tuesday.

From Barron's • Apr. 7, 2026

The essential preliminary to a supernova explosion is the generation by silicon fusion of a massive iron core.

From "Cosmos" by Carl Sagan