chemotherapy Syllabification: (che·mo·ther·a·py)Pronunciation: /ˌkēmōˈTHerəpē, ˌkemō-/Translate chemotherapy | into French | into German | into Italian | into Spanish Definition of chemotherapy noun the treatment of disease by the use of chemical substances, especially the treatment of cancer by cytotoxic and other drugs. Derivatives chemotherapistPronunciation: /-pist/ noun chemotherapy in other Oxford dictionaries Definition of chemotherapy in the British & World English dictionary