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

The National Institutes of Health warns that sleep deficiency can contribute to conditions like heart disease, kidney disease, high blood pressure, diabetes, stroke, obesity and depression. —Joseph Choi, The Hill, 3 Jan. 2026

Yet as dietary fat intake declined, obesity and diabetes rates surged. —Ezekiel J. Emanuel, CNBC, 2 Jan. 2026

The trial included roughly 450 adults with obesity or who were overweight and had knee osteoarthritis. —Berkeley Lovelace Jr, NBC news, 1 Jan. 2026

Rural counties have higher rates of obesity, smoking, diabetes and COPD rates, in addition to higher rates of teen births. —Alexandra Kukulka, Chicago Tribune, 1 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