plural germs
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

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.
Chicken and turkey carried the highest-risk strains of bacteria, but pork and beef also carried the illness-causing germs. Cara Lynn Shultz, PEOPLE, 24 Oct. 2025 In Toilet Base Regularly cleaning your toilet with water and vinegar will keep the smells away, but will also clean any of the germs that fester in and around your toilet and make the area stink, according to Knoll. Daley Quinn, Southern Living, 23 Oct. 2025 Dirt and germs breed bad odors. Nafeesah Allen, Better Homes & Gardens, 21 Oct. 2025 The immune system typically prevents these germs from causing infection in the lungs, but some can still evade the body's defenses, even if a person is in good health, according to the Mayo Clinic. Rebecca Cohen, NBC news, 16 Oct. 2025 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

Browse Nearby Words

Cite this Entry

“Germ.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/germ. Accessed 30 Oct. 2025.

Kids Definition

germ

noun
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
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

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