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

Earlier research from Shamsi's lab used single-cell RNA sequencing to identify SLIT3, a protein released by brown fat cells that may help them communicate.

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

In contrast, mice genetically engineered to make unusually high amounts of ACOX2 in brown fat showed increased heat production, better cold tolerance and improved insulin sensitivity and weight control when fed the same high-fat diet.

From Science Daily • Oct. 9, 2025

Mitochondria in brown fat can shift from making fuel to generating heat through a molecule called uncoupling protein 1.

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