insincerity insincerely • insinking · · · Info · Definitions · Synonyms · Antonyms · Characters · · insincerity · · Text Latin · · Script 11 · · Length Definitions · · · (noun) the quality of not being open or truthful; deceitful or hypocritical. Synonyms: falseness, hollowness. · · Noun Definition 1 Synonyms · · · falseness · · Synonym 1 hollowness · · Synonym 2 Antonyms · · · sincerity · · Antonym 0 Characters · · c latin small letter c U+0063 e latin small letter e U+0065 i latin small letter i U+0069 n latin small letter n U+006E r latin small letter r U+0072 s latin small letter s U+0073 t latin small letter t U+0074 y latin small letter y U+0079