faintness n. + Add to list US //ˈfeɪntnəs// UK //fˈeɪntnəs// faint·ness SynonymsAntonymsEtymology Synonyms dimnessfaintheartedness Antonyms stoutheartednessOriginMEfaintnesse→ENfaintness From Middle English faintnesse, feintnesse, equivalent to faint + -ness.