brown fat

American  

noun

1. brownish-yellow adipose tissue in the upper back, or interscapular, region of many mammals, most conspicuously in hibernating species and human newborns, composed of numerous innervated fat cells that can produce heat during cold stress; thermogenic tissue.

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brown fat British  

noun

1. tissue composed of a type of fat cell that dissipates as heat most of the energy released when food is oxidized; brown adipose tissue. It is present in hibernating animals and human babies and is thought to be important in adult weight control

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Etymology

Origin of brown fat

First recorded in 1950–55

Example Sentences

"By rapidly taking up and using fuel sources from our bodies and the food that we eat, brown fat acts like a metabolic sink that draws in nutrients and prevents them from being stored."

From Science Daily • Mar. 28, 2026

In contrast, targeting brown fat could increase how much energy the body uses.

From Science Daily • Mar. 28, 2026

Exposure to cold can increase the amount of brown fat, and scientists have long suggested that activating it could support weight loss by increasing calorie burning.

From Science Daily • Oct. 9, 2025

Conducted in mice, the research points to new possibilities for using brown fat to address metabolic conditions such as insulin resistance and obesity.

From Science Daily • Oct. 9, 2025

Suddenly they sighted just ahead a basket phaeton and a brown, fat pony hitched to it.

From The Corner House Girls on a Tour Where they went, what they saw, and what they found by Hill, Grace Brooks