- silicon, Si, atomic number 14 - a tetravalent nonmetallic element; next to oxygen it is the most abundant element in the earth's crust; occurs in clay and feldspar and granite and quartz and sand; used as a semiconductor in transistors
--1 is a kind of chemical element, element; semiconductor, semiconducting material
--1 is a substance ofsilicone, silicone polymer; clay; feldspar, felspar; granite; quartz; sand