a nonmetallic univalent element belonging to the halogens; usually a yellow irritating toxic flammable gas; a powerful oxidizing agent; recovered from fluorite or cryolite or fluorapatite
例句
用作名词(n.)
It is a compound of aluminum, silica and fluorine.它是铝、硅和氟的化合物。
Fluorin can avoid brown striation and whiten skins.氟能消除褐色斑,使皮肤变白。
