noun /ˌmaɪ.kɹəʊˈɔː.ɡən.ɪ.zəm̩,ˌmaɪ.kɹoʊˈɔːɹ.ɡən.ɪ.zəm̩/
An organism that is too small to be seen by the unaided eye, especially a single-celled organism, such as a bacterium.
The cud is then reswallowed and further digested by specialized microorganisms that live in the rumen.
See Also: microbe
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