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

In contrast, brown fat is present in smaller amounts and plays a specialized role in controlling body temperature and supporting metabolic health.

From Science Daily • Mar. 28, 2026

The researchers also identified a receptor called PLXNA1 that binds to one of the SLIT3 fragments and helps regulate nerve development in brown fat.

From Science Daily • Mar. 28, 2026

Researchers have discovered how a crucial protein switches on brown fat by helping it build the blood vessels and nerve connections needed for heat production.

From Science Daily • Mar. 28, 2026

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

They are about an inch long, gray and brown, fat and greasy-looking.

From Ontario Teachers' Manuals: Nature Study by Ontario. Ministry of Education