the GNU version of the Collaborative International Dictionary of English
n. One of the Protozoa.
n. A single zooid of a compound protozoan.
The Century Dictionary and Cyclopedia
n. An individual or a species of Protozoa; a protozoan.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. any of diverse minute acellular or unicellular organisms usually nonphotosynthetic
Word Usage
"The malarial haematozoon is a protozoon, a very small protozoon since it lives and develops in the red blood cells which in man have a diameter of only 7 microns."