Entry 1 sense Webster, 1913 Antimalarial /(ăn`tĭ*mȧ*lā"rĭ*al)/ · An·ti·ma·la·ri·al · IPA /ˌæn.ti.məˈlɛ.ɹi.əl/ 01 a. Good against malaria. 1. Good against malaria.