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protoctist

noun
  1. (in modern biological classifications) any unicellular or simple multicellular organism belonging to the kingdom Protoctista, which includes protozoans, algae, and slime moulds

Word Origin for protoctist

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
protoctist in Medicine

protoctist

[prō′tək-tĭst]
n.
  1. A eukaroytic, unicellular organism belonging to the kingdom Protoctista, which includes protozoa, slime molds, and certain algae.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
protoctist in Science

protoctist

[prə-tŏk′tĭst]
  1. See protist.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.