Silicon (Si) yog cov tshuaj tsis yog xim hlau uas muaj nyob rau hauv tsev neeg cov pa roj carbon (pab pawg 14 [IVa] ntawm lub sijhawm teem sijhawm). Silicon ua rau 27.7% ntawm lub ntiaj teb crust, yog qhov thib ob ntau tshaj plaws nyob rau hauv lub crust, thib ob tsuas yog oxygen. Nws yog ib qho nyuaj, nkig crystalline khoom nrog grey-xiav xim hlau lustre, thiab yog tetravalent metalloid thiab semiconductor.
Lub npe silicon los ntawm Latin silex lossis silicis, lub ntsiab lus 'flint' lossis 'hardstone'. Thawj qhov kev sib cais thiab kev piav qhia ntawm amorphous elemental silicon raws li ib qho khoom tau ua los ntawm Jons Jakob Berzelius, tus kws tshuaj Swedish, xyoo 1824. Kev tau txais cov khoom siv tsis huv silicon tau ua tiav thaum ntxov li 1811. Kev sib cais ntawm crystalline elemental silicon tsis tau paub txog txog thaum Xyoo 1854, thaum nws tau txais los ua khoom ntawm electrolysis.
