exterminate UK /ɛkˈstəː.mɪ.neɪt/US /ɪkˈstɝ.mɪ.neɪt/ verb2 •To kill or otherwise permanently eliminate all of (a population, often of pests or undesirables), usually intentionally.We'll use poison to exterminate the rats. •(figurative) To bring a definite end to; to finish completely.The public school failed to exterminate truancy. formsexterminated · exterminating · exterminates