|a chattering or flighty, light-headed person.|
|a calculus or concretion found in the stomach or intestines of certain animals, esp. ruminants, formerly reputed to be an effective remedy for poison.|
|See also protoctist (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 fungi|
|[C19: from New Latin Protista most primitive organisms, from Greek prōtistos the very first, from prōtos first]|
protist pro·tist (prō'tĭst)
A unicellular, eukaroytic organism belonging to the former taxonomic kingdom Protista.
|protist (prō'tĭst) Pronunciation Key
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.