body mass index

American  

[bod-ee mas in-deks] / ˈbɒd i ˌmæs ˌɪn dɛks /

noun

1. an index for assessing overweight and underweight, obtained by dividing body weight in kilograms by height in meters squared: a measure of 25 or more is considered overweight.

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body mass index British  

noun

1.  BMI.  an index used to indicate whether a person is over- or underweight. It is obtained by dividing a person's weight in kilograms by the square of their height in metres. An index of 20–25 is normal

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body mass index Scientific  

/ bŏd′ē /

1. A measurement of the relative percentages of fat and muscle mass in the human body, in which weight in kilograms is divided by height in meters squared. The result is used as an index of obesity.

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Etymology

Origin of body mass index

First recorded in 1955–60

Example Sentences

See Examples For:

body mass index

It also gave the president the exact height and weight ratio to keep him right under an “obese” body mass index, a designation so convenient as to be laughable.

From Salon ● Jun. 1, 2026

Current prescribing criteria center on body mass index thresholds and glycemic targets, metabolic markers that tell us something about a patient’s need for weight loss but nothing about their underlying GLP-1 physiology.

From Slate ● Mar. 22, 2026

Scientists are now locked in a fierce debate over the body mass index, and that could change who qualifies for a GLP-1 medication.

From MarketWatch ● Mar. 18, 2026

The standard way of categorising people's weight is by calculating their body mass index, or BMI.

From BBC ● Feb. 24, 2026

The asthma was under control, but the doctor alerted me to something else—Malia’s body mass index, a measure of health that factors together height, weight, and age, was beginning to creep up.

From "Becoming" by Michelle Obama