Definitions

1. noun

any of a group of single-celled eukaryotic organisms that are heterotrophic and are often parasitic or free-living in water or on other organisms.

“The protozoan parasite was identified in the patient’s blood sample.”

2. adjective

relating to or resembling protozoa, especially in being simple in structure and function.

“Protozoan organisms are often microscopic and can only be seen under a microscope.”