microbiome

American  

[mahy-kroh-bahy-ohm] / ˌmaɪ kroʊˈbaɪ oʊm /

noun

Microbiology.

1. the totality of microorganisms and their collective genetic material present in or on the human body or in another environment.

   The wide diversity of species that make up the microbiome is hard to fathom.

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Usage

What is a microbiome? A microbiome is a full collection of microorganisms and the genetic material of a living being or a specific environment. The term microbiome is most often used in reference to the human microbiome, and people will often discuss the microbiome without specifying that they mean the human variety. However, every living being has a microbiome. The microbiome includes all of the cells that make up a living body and all of the microorganisms that exist within it that promote healthy life processes, such as bacteria, fungi, and viruses. For example, there are hundreds of millions of bacteria and other organisms within the body that promote digestion, protect against pathogens and disease, and extract toxins from the body. All negative or outside organisms that enter the body also effectively become a part of the microbiome and will be considered when evaluating someone’s condition or health. Some of the first bacteria identified as living inside the bodies of healthy humans were E. coli, which aids digestion in the large intestine, and Veillonella parvula, which converts some harmful acids in the mouth into less harmful ones. In 2007, the scientific community launched a project called the Human Microbiome Project in order to learn more about these microorganisms. Example: The human microbiome includes so much more than bacteria and viruses.

Etymology

Origin of microbiome

Coined 2001 by Joshua Lederberg, American molecular biologist; micro(be) + biome

Compare meaning

How does microbiome compare to similar and commonly confused words? Explore the most common comparisons:

• microbiota vs. microbiome

Explanation

A microbiome is a tiny community made up entirely of microorganisms. This includes things like bacteria and fungi, and you can't escape them — they're everywhere, including inside your body right now! A biome is a specific environment with a specific climate, which contains particular kinds of animal and plant life. You can imagine a microbiome as a microscopic version of the same thing. It's essentially a tiny community of bacteria, fungi, and viruses all living together within a particular environment, such as the human gut.

Example Sentences

See Examples For:

microbiome

At the heart of current research is the oral microbiome, the community of hundreds of bacteria, fungi and other microbes that live in the mouth.

From The Wall Street Journal ● Jul. 26, 2026

The findings, published in Gut Microbes, introduce a new approach to cancer treatment that uses living bacteria to directly target tumors rather than simply altering the gut microbiome.

From Science Daily ● Jul. 10, 2026

O’Mara says the diet leads to a reduction in visceral fat, which wraps around organs, as well as a more robust microbiome, which can help with digestion.

From The Wall Street Journal ● Jun. 18, 2026

Another study found that higher citrus intake was associated with increased levels of beneficial gut bacteria and a lower risk of depression, suggesting a link between diet, the microbiome and mental health.

From The Wall Street Journal ● Jun. 14, 2026

Someone knocks into me, and I bump into a kid whose microbiome is 90 percent body spray.

From "The Miscalculations of Lightning Girl" by Stacy McAnulty