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

noun 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; atomic weight: 28.086; atomic number: 14; specific gravity: 2.4 at 20°C.

Origin of silicon

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

Can be confused

silicon silicone Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for silicon

British Dictionary definitions for silicon


/ (ˈsɪlɪkən) /


  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

Word Origin for silicon

C19: from silica, on the model of boron, carbon

Medicine definitions for silicon


[ sĭlĭ-kən, -kŏn′ ]

n. Symbol Si

A nonmetallic element occurring extensively in the earth's crust in silica and silicates, having both an amorphous and a crystalline allotrope and used in glass and semiconducting devices and in surgical implants. Atomic number 14.


Science definitions for silicon


[ sĭlĭ-kŏn′ ]


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. See Periodic Table.


Culture definitions for silicon


[ (sil-i-kon, sil-i-kuhn) ]

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