Any of a group of eukaryotic organisms belonging to the Kingdom Protista.
Protists do not have much in common apart from a relatively simple organization. They may occur as unicellular, multicellular, coenocytic, or colonial organisms.
Protists include: (1) protozoa, the animal-like protists, (2) algae, the plant-like protists, and (3) slime moulds and water moulds, the fungus-like protists.
Word origin: Greek protiston -a meaning the (most) first of all ones. The term protista was coined by Ernst Haeckel in 1866.
Related forms: protistan (adjective).
Derived terms: protistology.