Home › Words › S › supersinceritysupersinceritysupersincerity means the quality of being very sincere.Among words judged in Lexicurio's Arena, supersincerity ranks #456 of 42,747 for Qualifying.EtymologyFrom super- + sincerity.nounThe quality of being very sincere.Definitions & examples from Wiktionary (CC BY-SA 3.0).