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1. A number reflecting human weight in relationship to height, defined as weight in kilograms divided by the square of the height in meters
   - body mass index
    
2. A measure of someone's weight in relation to height; to calculate one's BMI, multiply one's weight in pounds by 703 and divide that by the square of one's height in inches; overweight is a BMI greater than 25; obese is a BMI greater than 30
   - body mass index

Type of: index, index number, indicant, indicator

Encyclopedia: BMI