microorganism

Meaning

1. 1nouncountable

   A living thing that is too small to be seen without a microscope, such as a bacterium or fungus.

   Grammar: Countable; use 'a microorganism' or 'microorganisms'.

   Patterns

   • a microorganism causes disease
   • microorganisms in the soil
   • harmful microorganism

   Some microorganisms are essential for breaking down food in our digestive system.

   The pond water was full of tiny microorganisms that we could see under the microscope.

   Not all microorganisms cause disease; many are beneficial.

Word forms

Common combinations

pathogenic microorganism

A pathogenic microorganism can cause serious illness.

soil microorganism

Soil microorganisms help decompose organic matter.

harmful microorganism

Not all bacteria are harmful microorganisms.

Synonyms and how they differ

microbe

Microbe is a more everyday word for the same thing, often used in news and general writing.

germ

Germ is informal and usually refers to a microorganism that causes disease.

Word family

microbial adjective

Relating to microorganisms.

Practice

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Write a sentence using “microorganism”, then check it and compare it with the examples above.

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