biologicalPronunciation: /bʌɪə(ʊ)ˈlɒdʒɪk(ə)l/Translate biological | into French | into German | into Italian | into Spanish Definition of biological adjective 1relating to biology or living organisms. (of a detergent or other cleaning product) containing enzymes to assist the process of cleaning. relating to or involving the use of microorganisms or toxins of biological origin as weapons of war. 2(of a parent or child) related by blood; natural:his biological mother noun (usually biologicals) a substance of biological origin used as a drug, vaccine, pesticide, etc.: a wide spectrum of biologicals are produced from animal cells in cultureDerivatives biologically adverb biological in other Oxford dictionaries Definition of biological in the US English dictionary