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.
Xenex LightStrike Infections acquired inside hospitals remain a serious problem, especially when harmful germs survive on surfaces after a patient leaves a room. — Atharva Gosavi, Interesting Engineering, 30 Aug. 2026 They’re born before antibodies – protective proteins that recognize incoming germs – can be transferred from mother to baby during the later stages of pregnancy. — Brenda Goodman, CNN Money, 28 Aug. 2026 Then there’s Baicapil, a blend of baikal skullcap (a flowering plant native to East Asia), wheat germ, and soybean germ extracts intended to encourage a healthy hair-growth cycle. — Christa Joanna Lee, Allure, 28 Aug. 2026 Climate change is spreading dangerous germs Our globalized food supply chain has a lot to do with our food safety — and that isn’t going to change any time soon. — Dylan Scott, Vox, 27 Aug. 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 1 Sep. 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
Last Updated: - Updated example sentences
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