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Any of numerous eukaryotic organisms that are not fungi, plants, or animals and are chiefly unicellular or colonial. Protists that are multicellular do not have cells differentiated into tissues. The protists include the protozoans, certain algae, oomycetes, and slime molds.

[From New Latin Prōtista, former kingdom name, from Greek prōtista, neuter pl. of prōtistos, the very first, superlative of prōtos, first; see per in Indo-European roots.]

pro·tis′tan (-tĭs′tən) adj. & n.
pro′tis·tol′o·gy (prō′tĭ-stŏl′ə-jē) n.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.protistan - free-living or colonial organisms with diverse nutritional and reproductive modes
microorganism, micro-organism - any organism of microscopic size
division Protista, Protista - eukaryotic one-celled living organisms distinct from multicellular plants and animals: protozoa, slime molds, and eukaryotic algae
References in periodicals archive ?
Depicting more accurate pictures of protistan community complexity using pyro sequencing of Hypervariable SSU rRNA gene regions.
Cockle Cerastoderma edule fishery collapse in the Ria de Arousa (Galicia, NW Spain) associated with the protistan parasite Marteilia cochillia.
Realtime PCR for detection and quantification of the protistan parasite Perkinsus marinus in environmental waters.
This library possessed many cellulase genes involved in protistan cellulose degradation, containing glycosyl hydrolase family 7.
and the protistan predator Oxyrrihs marina move more slowly in the presence of prey stimuli (Buskey and Stoecker 1989; Menden-Deuer and Grunbaum 2006).
Seeberi is in fact a protistan parasite that cannot be cultured.
Molecular Approaches for inferring evolutionary relationships among protistan parasites.
Biologists Mark Farmer and Andrea Habura point out in their paper that unicellular protistan evolution lasted 1 billion years, providing the genomic diversity from which multicellular organisms arose during that remarkably fertile period.
In the deep waters of lakes where rooted plants are unable to grow because sunlight does not penetrate to the bottom, it is the protistan community of planktonic algae and protozoa that underlies the lake's productivity.
Development and verification of a model for the population dynamics of the protistan parasite, Perkinsus marinus, within its host, the Eastern oyster, Crassostrea virginica, in Chesapeake Bay.