Meaning: けいそn. (Kanji=珪素) silicon, nonmetallic element which makes up more than one fourth of the earth's crust and is used in the manufacture of metal alloys and electronic components (Chemistry)n. (Kanji=硅素) silicon, nonmetallic element which makes up more than one fourth of the earth's crust and is used in the manufacture of metal alloys and electronic components (Chemistry)