Simple Definition of microbe

from our Learner's Dictionary

microbe

noun

ˈmaɪˌkroʊb How to pronounce microbe (audio)
plural microbes
: an extremely small living thing that can only be seen with a microscope : microorganism
a disease-causing microbe

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“Microbe.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/microbe. Accessed 22 Jun. 2026.

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