clack valve clack goose • clad · · · Info · Definitions · Synonyms · Characters · · clack valve · · Text Common · · Latin · · Scripts 11 · · Length 2 · · Syllables Definitions · · · (noun) a simple valve with a hinge on one side; allows fluid to flow in only one direction. Synonyms: clack valve, clack, clapper valve. · · Noun Definition 1 Synonyms · · · clack · · Synonym 1 clapper valve · · Synonym 2 Characters · · space U+0020 a latin small letter a U+0061 c latin small letter c U+0063 e latin small letter e U+0065 k latin small letter k U+006B l latin small letter l U+006C v latin small letter v U+0076