Any of a large group of single-celled, usually microscopic, eukaryotic organisms, such as amoebas, ciliates, flagellates, and sporozoans.(noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "protozoan" in a sentence
"Well, I suppose a protozoan could be a protagonist, added Charlotte."
"While the structure of this sentence is strictly accurate it has led several readers to point out that neither affliction results from a virus – babesia is a protozoan and fog fever is caused by the toxin 3-methylindole."
"You don't need to travel to a tropical location to contract a protozoan infection."