fluoride
/ˈflʊəraɪd/noun
mass noun
1- Chemistry a compound of fluorine with another element or group, especially salt of the anion F- or an organic compound with fluorine bonded to an alkyl group【化】氟化物。
1.1
- mass noun sodium fluoride or another fluorine-containing salt added to water supplies or toothpaste in order to reduce tooth decay（氢氟酸盐等有助于防止龋齿的）增氟剂。
词源
early 19th cent.: from FLUORINE + -IDE.