protozoan

[ proh-tuh-zoh-uhn ]
/ ˌproʊ təˈzoʊ ən /
Biology

noun, plural pro·to·zo·ans, (especially collectively) pro·to·zo·a [proh-tuh-zoh-uh]. /ˌproʊ təˈzoʊ ə/.

any of a diverse group of eukaryotes, of the kingdom Protista, that are primarily unicellular, existing singly or aggregating into colonies, are usually nonphotosynthetic, and are often classified further into phyla according to their capacity for and means of motility, as by pseudopods, flagella, or cilia.

adjective

of, relating to, or characteristic of a protozoan.

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Origin of protozoan

First recorded in 1860–65; Protozo(a) + -an
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Example sentences from the Web for protozoan

British Dictionary definitions for protozoan

protozoan
/ (ˌprəʊtəˈzəʊən) /

noun plural -zoa (-ˈzəʊə) or -zoans

Also called: protozoon (ˌprəʊtəˈzəʊɒn) plural -zoa any of various minute unicellular organisms formerly regarded as invertebrates of the phylum Protozoa but now usually classified in certain phyla of protoctists. Protozoans include flagellates, ciliates, sporozoans, amoebas, and foraminifers

adjective Also: protozoic

of or relating to protozoans

Word Origin for protozoan

C19: via New Latin from Greek proto- + zoion animal
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for protozoan

protozoan
[ prō′tə-zōən ]

n. pl. pro•to•zo•a (-zōə)

Any of a group of single-celled, usually microscopic, eukaryotic organisms, such as amoebas, ciliates, flagellates, and sporozoans.

Other words from protozoan

pro′to•zoan null null adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Scientific definitions for protozoan

protozoan
[ prō′tə-zōən ]

Plural protozoans protozoa

Any of a large group of one-celled organisms (called protists) that live in water or as parasites. Many protozoans move about by means of appendages known as cilia or flagella. Protozoans include the amoebas, flagellates, foraminiferans, and ciliates. Their traditional classification as the subkingdom Protozoa is still used for convenience, but it is now known that protozoans represent several evolutionarily distinct groups. See more at protist.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.