fluoridize
/ˈflʊərɪdʌɪz/ /ˈflɔːrɪdʌɪz/(also fluoridise)
verb
1 [with object] = fluoridate.
2 [with object] In wider use: to treat or combine with fluorine or fluoride; to convert into a fluoride.
Origin
1940s. From fluoride + -ize. Compare earlier fluoridized and slightly earlier fluoridization.