body mass index

noun

: a measure of body fat that is the ratio of the weight of the body in kilograms to the square of its height in meters

Examples of body mass index in a Sentence

A person with a body mass index of more than 30 is considered to be obese.
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.
The scientists followed participants for up to 14 years and examined how changes in body mass index, or BMI, and waist circumference were associated with the risk of death. — Faye Chiu, CNN Money, 26 Aug. 2026 Under the pilot, many Medicare beneficiaries with a body mass index of 35 or higher — the upper range of obesity — qualify for coverage of one of those drugs, if prescribed. — Jackie Fortiér, Miami Herald, 25 Aug. 2026 Eligibility depends on a detailed checklist of body mass index thresholds, specific combinations of chronic conditions, and prior treatment histories. — Jeffrey Millstein, STAT, 11 Aug. 2026 Additionally, the average body mass index was 23, so the results could differ for women with higher body weight. — Emily Kay Votruba, EverydayHealth.com, 6 Aug. 2026 See All Example Sentences for body mass index

Word History

First Known Use

1983, in the meaning defined above

Time Traveler
The first known use of body mass index was in 1983

Browse Nearby Words

body mark
body mass index
body mechanics
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Cite this Entry

“Body mass index.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/body%20mass%20index. Accessed 1 Sep. 2026.

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Kids Definition

body mass index

noun
: a measure of body fat that is the ratio of the weight of the body in kilograms to the square of its height in meters

Medical Definition

body mass index

noun
: a measure of body fat that is the ratio of the weight of the body in kilograms to the square of its height in meters
a body mass index in adults of 25 to 29.9 is considered an indication of overweight, and 30 or more an indication of obesity
—abbreviation BMI

called also Quetelet index

More from Merriam-Webster on body mass index

Britannica.com: Encyclopedia article about body mass index

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