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

Scientists have uncovered a molecular "switch" in mice that turns on a hidden energy-burning system inside brown fat, a discovery that could eventually help researchers develop new treatments for bone disease.

From Science Daily • May 12, 2026

When exposed to cold, brown fat uses glucose and lipids to produce heat through a process called thermogenesis.

From Science Daily • Mar. 28, 2026

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

Mice that lacked ACOX2 in their brown fat were less able to tolerate cold, showed lower body temperatures after exposure to cold, and had poorer insulin sensitivity.

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