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adjective an·aer·o·bic \ˌa-nə-ˈrō-bik; ˌan-ˌer-ˈō-\

Simple Definition of anaerobic

  • of exercise : strengthening muscles by forcing them to work very hard for a brief time

  • : not using oxygen

Source: Merriam-Webster's Learner's Dictionary

Full Definition of anaerobic

  1. 1 a :  living, active, occurring, or existing in the absence of free oxygen <anaerobic respiration> <anaerobic bacteria> b :  of, relating to, or being activity in which the body incurs an oxygen debt <anaerobic exercise>

  2. 2 :  relating to or induced by anaerobes


play \-bi-k(ə-)lē\ adverb

Examples of anaerobic in a sentence

  1. Weight lifting is an anaerobic exercise.

  2. Some bacteria are aerobic and others are anaerobic.

Did You Know?

In Greek, the prefix a- or an- means "not" or "without", and bios means "life". Anaerobic sports and exercise, such as gymnastics, weight lifting, and sprinting, are of high intensity but short duration, so they don't involve much oxygen intake. Anaerobic exercise triggers a different type of cell activity from aerobic exercise. As a result, it doesn't do much for your heart and lungs and it doesn't burn off fat; what it does do is build muscle. Anaerobic bacteria are bacteria that live without oxygen. They're responsible for several nasty conditions, including tetanus, gangrene, botulism, and food poisoning. They often live in deep wounds, so a bad dog bite—or, even worse, a human bite—can be dangerous, since the mouth is full of anaerobic bacteria. But most anaerobic bacteria are harmless, and many are essential to our lives.

Circa 1881

First Known Use of anaerobic

circa 1881

Medical Dictionary


play play
adjective an·aer·o·bic \ˌan-ə-ˈrō-bik; ˌan-ˌa(-ə)r-ˈō-, -ˌe(-ə)r-\

Medical Definition of anaerobic

  1. 1a:  living, active, or occurring in the absence of free oxygen <during heavy exercise anaerobic respiration occurs, pyruvic acid acts as a hydrogen acceptor, and lactic acid builds up in the tissues> <anaerobic bacteria>b (1):  of, relating to, or being activity in which the body incurs an oxygen debt <an anaerobic workout> <Anaerobic activities like sprinting and weight lifting, on the other hand, burn carbohydrates without using oxygen …—Jane E. Brody, The New York Times, 28 Sept. 1986> (2):  of or relating to the body's ability to incur an oxygen debt <Your anaerobic threshold is basically how long you can last without breathing (your lungs working in oxygen debt) while, say, sprinting or going as hard as you can on a bike or in the pool.—Bob Condor, The Seattle Post-Intelligencer, 22 Sept. 2008>

  2. 2:  relating to or induced by anaerobes


\-bi-k(ə-)lē\play adverb

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