- (in modern biological classifications) any unicellular or simple multicellular organism belonging to the kingdom Protoctista, which includes protozoans, algae, and slime moulds
C19: from New Latin protoctista, perhaps from Greek prototokos first born
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
- A eukaroytic, unicellular organism belonging to the kingdom Protoctista, which includes protozoa, slime molds, and certain algae.
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- See protist.
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