protist

noun

pro·​tist ˈprō-(ˌ)tist 

: any of a diverse taxonomic group and especially a kingdom (Protista synonym Protoctista) of eukaryotic organisms that are unicellular and sometimes colonial or less often multicellular and that typically include the protozoans, most algae, and often some fungi (such as slime molds)

protistan

prō-ˈti-stən 

adjective or noun

Examples of protist in a Sentence

Recent Examples on the Web

If that didn’t prevent the irritation, the protists used their cilia to spit water at the pipette. —Claire L. Evans, Quanta Magazine, 30 July 2025

Slime molds are now classified as protists, placing them in the same category as most algae. —Joshua Siskin, Oc Register, 5 June 2025

Know Algae Types Algae can encompass many types of protists. —Lauren David, Better Homes & Gardens, 16 Apr. 2025

Once hypothesized as a jellyfish, fungus or even a giant protist, science now favors an animal interpretation. —Scott Travers, Forbes.com, 14 Apr. 2025

Word History

Etymology

New Latin Protista, from Greek, neuter plural of prōtistos very first, primal, from superlative of prōtos first — more at proto-

First Known Use

1873, in the meaning defined above

Kids Definition

protist

noun

pro·​tist ˈprōt-əst 

: any of a kingdom of organisms that resemble plants or animals or both, are one-celled and sometimes colonial or less often many-celled, and that typically include the protozoans, most algae, and often some fungi (as slime molds)

protistan

prō-ˈtis-tən 

adjective or noun

Medical Definition

protist

noun

pro·​tist ˈprōt-əst, ˈprō-ˌtist 

: any of a diverse taxonomic group and especially a kingdom (Protista synonym Protoctista) of eukaryotic organisms that are unicellular and sometimes colonial or less often multicellular and that typically include the protozoans, most algae, and often some fungi (as slime molds)

protistan

prō-ˈtis-tən 

adjective or noun