IPA: /məˈlɛəriəs/
KK: /mælˈɛəriəs/
Relating to or causing a disease transmitted by mosquitoes, specifically malaria.
The malarious regions are often at higher risk for outbreaks of malaria.
Malarious → It is formed from "malar" (from Latin *malaris*, meaning relating to the cheek or jaw) and the suffix "-ious" (meaning full of or characterized by). The word "malarious" refers to something characterized by or relating to the malar region, often used in a medical context to describe conditions associated with the cheek area.
Think of 'malar' relating to the cheek area, and remember that 'malarious' means full of characteristics related to the cheeks.