meperidine hydrochloride meperidine • mephaquine · · · Info · Definitions · Synonyms · Characters · · meperidine hydrochloride · · Text Common · · Latin · · Scripts 24 · · Length 8 · · Syllables Definitions · · · (noun) a synthetic narcotic drug (trade name Demerol) used to treat pain. Synonyms: meperidine, meperidine hydrochloride, Demerol. · · Noun Definition 1 Synonyms · · · meperidine · · Synonym 1 demerol · · Synonym 2 Characters · · space U+0020 c latin small letter c U+0063 d latin small letter d U+0064 e latin small letter e U+0065 h latin small letter h U+0068 i latin small letter i U+0069 l latin small letter l U+006C m latin small letter m U+006D n latin small letter n U+006E o latin small letter o U+006F p latin small letter p U+0070 r latin small letter r U+0072 y latin small letter y U+0079