microorganism
my-kroh-OR-guh-niz-um
Microorganism (noun) means a living thing too small to be seen without a microscope, especially a single-celled one such as a bacterium. Example: “Boiling the water kills most harmful microorganisms.”
noun
1
A living thing too small to be seen without a microscope, especially a single-celled one such as a bacterium.
"Boiling the water kills most harmful microorganisms."
"Yoghurt is made with the help of friendly microorganisms."
"A single spoonful of soil contains countless microorganisms."
How to use microorganism
Learner’s notesIn plain EnglishA living thing so tiny you need a microscope to see it.
When to use it
It is a fairly technical word, while microbe is the shorter everyday alternative.
Memory tip
The stress falls on the third syllable, as in my-kroh-OR-guh-niz-um.
Trace the full origin ↓
Common pairings
harmful microorganisms
kill microorganisms
microorganisms in the soil
growth of microorganisms
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Boiling the water kills most harmful _____.
Etymology
English formed the word by joining the prefix micro- to organism.
Synonyms
View more →Related words
Rhymes for microorganism
humanism
veganism
organism
shamanism
mechanism
hooliganism
vegetarianism
republicanism
equestrianism
utilitarianism
authoritarianism
See all rhymes for microorganism →
Frequently asked questions
What is a microorganism?
A microorganism is a living thing so small that you need a microscope to see it. Bacteria are a common example.
Is microorganism spelled with a hyphen?
Both microorganism and micro-organism exist, but microorganism is the more common spelling in print and in most dictionaries.
Is a virus a microorganism?
It depends on how strictly the word is used. Casually, viruses are often included, but in precise terms they are not always counted.
What is the meaning of microorganism?
"microorganism" (noun) means a living thing too small to be seen without a microscope, especially a single-celled one such as a bacterium.
