clumsiness n. + Add to list US //ˈkɫəmzinəs// UK //klˈʌmzɪnəs// clum·si·ness SynonymsAntonymsEtymology Synonyms awkwardnessgracelessnessineptitudeineptnessmaladroitnessslownessstiffness Antonyms gracefulnessOrigin From clumsy + -ness.