trephine trephination • trephiner · · · Info · Definitions · Synonyms · Characters · · trephine · · Text Latin · · Script 8 · · Length Definitions · · · (noun) a surgical instrument used to remove sections of bone from the skull. Synonyms: trepan. · · Noun Definition 1 (verb) operate on with a trephine. · · Verb Definition 1 Synonyms · · · trepan · · Synonym 1 Characters · · e latin small letter e U+0065 h latin small letter h U+0068 i latin small letter i U+0069 n latin small letter n U+006E p latin small letter p U+0070 r latin small letter r U+0072 t latin small letter t U+0074