[ proh-tist ]
/ ˈproʊ tɪst /
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noun Microbiology
any of various one-celled organisms, classified in the kingdom Protista, that are either free-living or aggregated into simple colonies and that have diverse reproductive and nutritional modes, including the protozoans, eukaryotic algae, and slime molds: some classification schemes also include the fungi and the more primitive bacteria or may distribute the organisms between the kingdoms Plantae and Animalia according to dominant characteristics.


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Origin of protist

First recorded in 1870–75; from German Protist (masculine singular), from New Latin Protista (neuter plural) name of the kingdom, from Greek prṓtistos (masculine singular) “the very first,” superlative of prôtos “first”; see proto-


pro·tis·tan [proh-tis-tuhn], /proʊˈtɪs tən/, adjective, nounpro·tis·tic [proh-tis-tik], /proʊˈtɪs tɪk/, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use protist in a sentence

British Dictionary definitions for protist

/ (ˈprəʊtɪst) /

(in some classification systems) any organism belonging to the kingdom Protista, originally including bacteria, protozoans, algae, and fungi, regarded as distinct from plants and animals. It was later restricted to protozoans, unicellular algae, and simple fungiSee also protoctist

Word Origin for protist

C19: from New Latin Protista most primitive organisms, from Greek prōtistos the very first, from prōtos first
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 protist

[ prōtĭst ]

A unicellular, eukaroytic organism belonging to the former taxonomic kingdom Protista.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Scientific definitions for protist

[ prōtĭst ]

Any of a large variety of usually one-celled organisms belonging to the kingdom Protista (or Protoctista). Protists are eukaryotes and live in water or in watery tissues of organisms. Some protists resemble plants in that they produce their own food by photosynthesis, while others resemble animals in consuming organic matter for food. Protist cells are often structurally much more elaborate than the cells of multicellular plants and animals. Protists include the protozoans, most algae, diatoms, oomycetes, and the slime molds. Also called protoctist See Table at taxonomy.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.