antimetabolite: an antineoplastic drug that inhibits the utilization of a metabolite
antineoplastic: any of several drugs that control or kill neoplastic cells; used in chemotherapy to kill cancer cells; all have unpleasant side effects that may include nausea and vomiting and hair loss and suppression of bone marrow function
pyxidium: fruit of such plants as the plantain; a capsule whose upper part falls off when the seeds are released