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English definition of “microorganism”

microorganism

noun [C]    /ˌmɑɪ·kroʊˈɔr·ɡəˌnɪz·əm/
biology a living thing which on its own is too small to be seen without a microscope (= device that makes small objects look larger)
(Definition of microorganism noun from the Cambridge Academic Content Dictionary © Cambridge University Press)
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