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.

---

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

---

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.

---

Etymology

Origin of body mass index

First recorded in 1955–60

Example Sentences

See Examples For:

body mass index

The once-daily pill is approved for patients with a body mass index of at least 30, or between 27 and 30 if there is at least one weight-related health condition.

From The Wall Street Journal ● Aug. 24, 2026

More important, in order to qualify, Medicare patients must have a higher body mass index than the rest of the U.S. population needs to have in order to take these drugs.

From MarketWatch ● Jun. 25, 2026

Machines in supermarkets, leisure centres and libraries can assess body mass index, blood pressure, heart health and body fat in around ten minutes.

From BBC ● Jun. 21, 2026

The participants had a median age of 69 years and a median body mass index of 28.4.

From Science Daily ● Jun. 17, 2026

I was sure it was just about his body mass index or the tensile strength of his ligaments, but still, he had her ear and he wasn’t using it to talk me up.

From "Liar, Liar" by Gary Paulsen