obesity

noun

obe·​si·​ty ō-ˈbē-sə-tē 

: a condition characterized by the excessive accumulation and storage of fat in the body

Obesity affects not just appearance, but disease processes as well.

—Malorye Allison

Synonyms of obesity

• fatness
• fat
• weight
• adiposity
• corpulence

Examples of obesity in a Sentence

obesity has been linked to a number of health risks, such as heart disease

Recent Examples on the Web

Here’s how obesity pills could reshape the space. —Annika Kim Constantino, CNBC, 10 Jan. 2026

Our Pediatric Health Lifestyle Center, which is an incredibly successful program that operates on our pediatric outpatient clinics, is a lifestyle modification program for kids that are screened at risk for diabetes and obesity and includes consultation with nutritionists. —Grace Hase, Mercury News, 9 Jan. 2026

There’s similar progress on obesity and cancer, as well as on problems in developing countries like malaria, TB, and malnutrition. —Eleanor Pringle, Fortune, 9 Jan. 2026

Ghanem added that body composition analyzers, like DEXA scans, will likely be more widely used as awareness grows about the limitations of BMI and weight in assessing obesity. —Angelica Stabile, FOXNews.com, 9 Jan. 2026

Word History

Etymology

borrowed from Middle French & Latin; Middle French obesité, borrowed from Latin obēsitāt-, obēsitās, from obēsus "fat, stout" + -itāt-, -itās -ity — more at obese

First Known Use

circa 1611, in the meaning defined above

Phrases Containing obesity

• anti-obesity

Medical Definition

obesity

noun

obe·​si·​ty ō-ˈbē-sət-ē 

plural obesities

: a condition that is characterized by excessive accumulation and storage of fat in the body and that in an adult is typically indicated by a body mass index of 30 or greater