germ

noun

ˈjərm How to pronounce germ (audio)
plural germs
Synonyms of germnext
1
a
: a small mass of living substance capable of developing into an organism or one of its parts
b
: the embryo with the scutellum of a cereal grain that is usually separated from the starchy endosperm during milling
2
: something that initiates development or serves as an origin : rudiments, beginning
3
: a microorganism causing disease : a pathogenic agent (such as a bacterium or virus)
broadly : microorganism

Synonyms of germ

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Examples of germ in a Sentence

the germ that causes tuberculosis the germ of an idea the germ layers of an embryo
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Always assume items have unseen germs or pests and clean them accordingly before bringing them into your home. — Brandee Gruener, Southern Living, 1 Aug. 2026 Cofounded by Juliette Lailler and Marie Belile, Krème touts clean, creamy formulations and focuses on nourishing the skin’s microbiome, which shields against germs, pathogens and inflammation. — Samantha Conti, Footwear News, 31 July 2026 She has been diagnosed with retinitis pigmentosa, an eye disease that causes vision loss, and lupus, a disease where the immune system mistakenly attacks healthy tissues and organs instead of fighting germs, according to court records. — Chase Jordan july 30, Charlotte Observer, 30 July 2026 Diarrhea Once water has been contaminated by germs that cause contagious diarrhea, a swimmer only has to swallow a tiny amount to become infected. — Amanda MacMillan, Health, 30 July 2026 See All Example Sentences for germ

Word History

Etymology

French germe, from Latin germin-, germen, from gignere to beget — more at kin

First Known Use

circa 1550, in the meaning defined at sense 2

Time Traveler
The first known use of germ was circa 1550

Phrases Containing germ

Rhymes for germ

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Browse Nearby Words

Gerlachovsky
germ
German
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Cite this Entry

“Germ.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/germ. Accessed 5 Aug. 2026.

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Kids Definition

germ

noun
ˈjərm How to pronounce germ (audio)
1
a
: a small mass of living substance capable of developing into a whole individual or one of its parts
b
: the embryo in the seed of a cereal (as corn or wheat) together with its cotyledon that is usually separated from the starchy part of the seed during milling
2
: something that serves as an origin
the germ of an idea
3
: a microscopic living thing
especially : one that causes disease

Medical Definition

germ

noun
ˈjərm How to pronounce germ (audio)
1
: a small mass of living substance capable of developing into an organism or one of its parts
2
: a microorganism causing disease : a pathogenic agent (as a bacterium or virus)
broadly : microorganism

More from Merriam-Webster on germ

Nglish: Translation of germ for Spanish Speakers

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