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Synonyms

germ

American  
[jurm] / dʒɜrm /

noun

  • germs
    plural
  1. a microorganism, especially when disease-producing; microbe.

  2. a bud, offshoot, or seed.

  3. the rudiment of a living organism; an embryo in its early stages.

  4. the initial stage in development or evolution, as a germ cell or ancestral form.

    Synonyms:
    seed, rudiment, bud, root, spark
  5. something that serves as a source or initial stage for subsequent development.

    the germ of an idea.


adjective

  1. Pathology. of, relating to, or caused by disease-producing germs.

germ British  
/ dʒɜːm /

noun

  1. a microorganism, esp one that produces disease in animals or plants

  2. (often plural) the rudimentary or initial form of something

    the germs of revolution

  3. a simple structure, such as a fertilized egg, that is capable of developing into a complete organism

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

germ Scientific  
/ jûrm /
  1. A microscopic organism or agent, especially one that is pathogenic, such as a bacterium or virus.


Usage

The terms germ and microbe have been used to refer to invisible agents of disease since the nineteenth century, when scientists introduced the germ theory of disease, the idea that infections and contagious diseases are caused by microorganisms. Microbe, a shortening and alteration of microorganism, comes from the Greek prefix mikro–, “small,” and the word bios, “life.” Scientists no longer use the terms germ and microbe very much. Today they can usually identify the specific agents of disease, such as individual species of bacteria or viruses. To refer generally to agents of disease, they use the term pathogen, from the Greek pathos, “suffering,” and the suffix –gen, “producer.” They use microorganism to refer to any unicellular organism, whether disease-causing or not.

Other Word Forms

Derived Forms

Inflected Forms

Nouns

Etymology

Origin of germ

1400–50; late Middle English < Middle French germe < Latin germen shoot, sprout, by dissimilation from *genmen, equivalent to gen- ( see genitor, genus) + -men resultative noun suffix)

Explanation

A germ is a tiny life form that spreads disease. Germs are also small things that grow into larger things — whether animals, plants, or ideas. Germ is not a technical term, but you've probably heard it used in reference to tiny organisms (such as bacteria) that cause disease. A germ is also any small structure, such as a fertilized egg, that grows into something larger. A seed that grows into a plant is a germ. In some cases, you can talk about ideas as germs. The inspiration for a book or movie can be described as the germ of the project. Germs are small, but they start big things.

Keep Reading on Vocabulary.com

Vocabulary lists containing germ

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

The move to sell Reckitt’s hygiene business comes after changes made last year to the EU’s sanctions package on businesses operating in Russia hit locally produced germ protection and cleaning products.

From The Wall Street Journal Jul. 24, 2026

Spermidine is produced naturally by human cells and is also present in foods including wheat germ, mushrooms, parmesan, and cheddar.

From Science Daily Jul. 21, 2026

Weeks later, doctors discovered he had staph infection - which is caused by staphylococcus, a germ that lives in the nose of one in three people and can enter the body through a cut.

From BBC Mar. 28, 2026

"Between 10-24 per cent of the population unknowingly carry this germ at the back of their throats usually without any harm," said Lee.

From Barron's Mar. 19, 2026

Which means she’s landed here and hasn’t caught the Noise germ yet.

From "The Knife of Never Letting Go" by Patrick Ness

"He obviously wants to be careful that people can't necessarily track him down. It shows someone who's paranoid about his personal safety – from germs or assassination attempts," says Fiona Hill.

From BBC May 30, 2026

He studied the prevention and cure of disease and how the body functioned, including respiration and blood circulation, and he had a nascent understanding of germs.

From The Wall Street Journal Apr. 14, 2026

Cleaning air filters removes dust, pet hair and germs, and — the best part — replacing them is inexpensive and easy.

From MarketWatch Feb. 28, 2026

Antibiotics are another standard treatment, and doctors are growing reluctant to prescribe them widely because of the spread of antibiotic-resistant germs.

From Barron's Feb. 3, 2026

The differences between those trajectories were stamped by continental differences in domesticable plants and animals, germs, times of settlement, orientation of continental axes, and ecological barriers.

From "Guns, Germs, and Steel: The Fates of Human Societies" by Jared M. Diamond

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