mental deficiency mental defectiveness • mental dexterity · · · Info · Definitions · Synonyms · Characters · · mental deficiency · · Text Common · · Latin · · Scripts 17 · · Length 6 · · Syllables Definitions · · · (noun) mild mental retardation. Synonyms: moronity, mental deficiency. · · Noun Definition 1 Synonyms · · · moronity · · Synonym 1 Characters · · space U+0020 a latin small letter a U+0061 c latin small letter c U+0063 d latin small letter d U+0064 e latin small letter e U+0065 f latin small letter f U+0066 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 t latin small letter t U+0074 y latin small letter y U+0079