locus coeruleus

noun

locus coe·​ru·​le·​us -si-ˈrü-lē-əs How to pronounce locus coeruleus (audio)
variants or less commonly locus ceruleus
: a bluish area of the brain stem with many norepinephrine-containing neurons

Examples of locus coeruleus in a Sentence

Recent Examples on the Web
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From there, the vagus nerve’s signals travel to other important brain structures with bewildering Latin names, such as the locus coeruleus and the dorsal raphe nuclei. — IEEE Spectrum, 29 May 2015 Holmes’s research on rats and mice shows that even moderate exercise can activate the locus coeruleus, a small brainstem nucleus that is important for attention, arousal, motivation and cognitive function. — Kelyn Soong, Anchorage Daily News, 3 Feb. 2023

Word History

Etymology

New Latin, literally, dark blue place

First Known Use

1852, in the meaning defined above

Time Traveler
The first known use of locus coeruleus was in 1852

Browse Nearby Words

locus classicus
locus coeruleus
locus in quo
See all Nearby Words

Cite this Entry

“Locus coeruleus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/locus%20coeruleus. Accessed 29 Mar. 2025.

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Medical Definition

locus coeruleus

noun
lo·​cus coe·​ru·​le·​us
variants also locus ceruleus
ˌlō-kə(s)-si-ˈrü-lē-əs How to pronounce locus coeruleus (audio)
plural loci coerulei also loci cerulei -lē-ˌī How to pronounce locus coeruleus (audio)
: a blue area of the brain stem with many norepinephrine-containing neurons
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