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 per1 in the Appendix of Indo-European roots.]
pro·tistan (-tĭstən) adj. & n.
pro′tis·tolo·gy (prō′tĭ-stŏlə-jē) n.
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