semilunar valve semilunar cartilage • semilunare · · · Info · Definitions · Characters · · semilunar valve · · Text Common · · Latin · · Scripts 15 · · Length 5 · · Syllables Definitions · · · (noun) a heart valve with cusps shaped like half-moons; prevents blood from flowing back into the heart. Synonyms: semilunar valve. · · Noun Definition 1 Characters · · space U+0020 a latin small letter a U+0061 e latin small letter e U+0065 i latin small letter i U+0069 l latin small letter l U+006C m latin small letter m U+006D n latin small letter n U+006E r latin small letter r U+0072 s latin small letter s U+0073 u latin small letter u U+0075 v latin small letter v U+0076