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

Meanwhile, the share of people with a body mass index at or above 30 decreased by more than 21% three months after switching to oral Wegovy. — Annika Kim Constantino, CNBC, 30 Sep. 2026

Strikingly, at the end of 80 weeks, about six out of 10 participants in the 12-mg group were no longer considered to have obesity based on their body mass index, according to Eli Lilly. — Jackie Flynn Mogensen, Scientific American, 29 Sep. 2026

During sign out, when doctors tell each other about patients at shift change, body mass index was a constant source of eye rolls and jokes. — Jessica Rosenblum, STAT, 8 Sep. 2026

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

Word History

First Known Use

1983, in the meaning defined above

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