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

Drugs like retatrutide may be most appropriate for someone who has a body mass index above 45 – above 30 is considered obese – and for whom existing drugs haven’t worked sufficiently, Dushay said. —Meg Tirrell, CNN Money, 19 Mar. 2026

Hasslers were also associated with multiple adverse mental and physical health outcomes like depression, anxiety and higher body mass index. —Sara Moniuszko, USA Today, 9 Mar. 2026

Even after the participants with obesity had lost about 25 percent of their body mass index after their surgery, some of their genes remained out of whack. —Lori Youmshajekian, Scientific American, 26 Feb. 2026

The cutoffs for healthy weight based on body mass index (BMI) are plagued by the shortcomings of BMI itself, which should not be used as the only determinant of complicated obesity. —Jody Dushay, STAT, 19 Feb. 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