meperidine mepacrine • meperidine hydrochloride · · · Info · Definitions · Synonyms · Characters · · meperidine · · Text Latin · · Script 10 · · Length 4 · · Syllables Definitions · · · (noun) a synthetic narcotic drug (trade name Demerol) used to treat pain. Synonyms: meperidine hydrochloride, Demerol. · · Noun Definition 1 Synonyms · · · meperidine hydrochloride · · Synonym 1 demerol · · Synonym 2 Characters · · d latin small letter d U+0064 e latin small letter e U+0065 i latin small letter i U+0069 m latin small letter m U+006D n latin small letter n U+006E p latin small letter p U+0070 r latin small letter r U+0072