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

The participants were between 18 and 60 years old with a body mass index (BMI) of 27 to 46, which is considered overweight or obese by the Centers for Disease Control and Prevention. —Angelica Stabile, FOXNews.com, 9 Apr. 2025

All of the participants were considered overweight or obese based on their body mass index (BMI).3 The studies looked at water aerobics interventions such as aqua Zumba, water yoga, and aqua jogging that lasted between 6 and 12 weeks. —Kristen Fischer, Health, 9 Apr. 2025

The research analyzed waist-to-hip ratio instead of body mass index to get a better indication of belly fat. —Tom Gavin, EverydayHealth.com, 24 Mar. 2025

That said, the current medical classifications for overweight and obesity are far from perfect—they’re based on body mass index (BMI), which doesn’t capture the full picture of a person’s health. —Erica Sloan, SELF, 13 Mar. 2025

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