biological clock biological attack • biological defence · · · Info · Definitions · Characters · · biological clock · · Text Common · · Latin · · Scripts 16 · · Length 5 · · Syllables Definitions · · · (noun) an innate mechanism in living organisms that controls the periodicity of many physiological functions. Synonyms: biological clock. · · Noun Definition 1 Characters · · space U+0020 a latin small letter a U+0061 b latin small letter b U+0062 c latin small letter c U+0063 g latin small letter g U+0067 i latin small letter i U+0069 k latin small letter k U+006B l latin small letter l U+006C o latin small letter o U+006F