A medicinal drug used to prevent or treat malaria WordNet 3.0 & Open English WordNet

Antimalarial medications or simply antimalarials are a type of antiparasitic chemical agent, often naturally derived, that can be used to treat or to prevent malaria, in the latter case, most often aiming at two susceptible target groups, young children and pregnant women. Wikipedia

Agents used in the treatment of malaria Wikidata

An agent that prevents or counteracts malaria. Wiktionary

Agent that prevents or counteracts malaria. Wiktionary (translation)