brown fat

noun

: a mammalian heat-producing tissue occurring especially in human fetuses and newborn infants and in hibernating animals

called also brown adipose tissue

Examples of brown fat in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
In order to generate heat, the brown fat cells need to draw on energy reserves stored in other fat cells. — Diana Hubbell, Popular Science, 10 Sep. 2025 It's even being studied as a promising obesity treatment, where it was shown to boost brown fat burn and encourage white fat to turn brown in mice. — New Atlas, 16 Nov. 2025 This study suggests that the brain’s recollection of cold can act as a switch, turning on the metabolic furnace of brown fat even when the surrounding air is mild. — William A. Haseltine, Forbes.com, 20 Aug. 2025 These cells arise within white fat depots under certain conditions – such as cold exposure or specific hormonal signals – and acquires some of the heat-producing properties of brown fat. — Claudio Villanueva, The Conversation, 11 Mar. 2026 See All Example Sentences for brown fat

Word History

First Known Use

1902, in the meaning defined above

Time Traveler
The first known use of brown fat was in 1902

Rhymes for brown fat

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Browse Nearby Words

brownface
brown fat
brown felt blight
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Cite this Entry

“Brown fat.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/brown%20fat. Accessed 7 Jul. 2026.

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Medical Definition

brown fat

noun
: a mammalian heat-producing tissue occurring especially in human fetuses and newborn infants and in hibernating animals

called also brown adipose tissue

Last Updated: - Updated example sentences
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