ossify v. + Add to list US //ˈɑsəˌfaɪ// UK //ˈɒsɪfˌaɪ// os·si·fy Archaic SynonymsEtymology Synonyms petrifyrigidifyOriginLATos→FRAossifier→ENossify Back-formation from ossification, or modeled on French ossifier and formed from Latin os, ossis (“bone”) + -ify.