Silicon is a
chemical element with symbol
Si and
atomic number 14. It is a
tetravalent metalloid, more reactive than
germanium, the metalloid directly below it in the table. Controversy about silicon's character dates to its discovery. It was first prepared and characterized in pure form in 1823. In 1808, it was given the name silicium (from , hard stone or
flint), with an
-ium word-ending to suggest a metal, a name which the element retains in several non-English languages. However, its final English name, first suggested in 1817, reflects the more physically similar elements
carbon and
boron.