n 1 : a product of metabolism: a : a metabolic waste usu. more or less toxic to the organism producing it : EXCRETION b : a product of one metabolic process that is essential to another such process in the same organism c : a metabolic waste of one organism that is markedly toxic to another : ANTIBIOTIC 2 : a substance essential to the metabolism of a particular organism or to a particular metabolic process .
Similar sounding terms: mu·ta·bil·i·ty
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