antimetabolite Syllabification: (an·ti·me·tab·o·lite)Pronunciation: /ˌantēmiˈtabəˌlīt, ˌantī-/Definition of antimetabolite noun Physiology a substance that interferes with the normal metabolic processes within cells, typically by combining with enzymes. antimetabolite in other Oxford dictionaries Definition of antimetabolite in the British & World English dictionary