microorganism: Meaning and Definition of

mi•cro•or•gan•ism

Pronunciation: (mī"krō-ôr'gu-niz"um), [key]
— n.
  1. any organism too small to be viewed by the unaided eye, as bacteria, protozoa, and some fungi and algae.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.
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