Order Haemosporidia is a group of parasitic protozoans that primarily cause malaria in humans and animals. The term Haemosporidia is derived from the Greek words haima, meaning blood, and sporos, meaning seed. There are several synonyms for the term Order Haemosporidia, including Plasmodiidae, Plasmodium species, and malaria parasites. These synonyms are often used interchangeably to describe the same group of parasitic protozoans. However, recent taxonomic changes have divided the Order into several suborders, including Aconoidasida, Haemospororida, and Haemoproteida. Despite these changes, the term Order Haemosporidia remains in use among researchers and medical professionals as a general descriptor for the group of organisms that cause malaria.