suprachiasmatic nucleus

noun

su·​pra·​chi·​as·​mat·​ic nucleus ˌsü-prə-ˌkī-əz-ˈma-tik- How to pronounce suprachiasmatic nucleus (audio)
: either of a pair of neuron clusters in the hypothalamus situated directly above the optic chiasma that receive photic input from the retina via the optic nerve and that regulate the body's circadian rhythms

Examples of suprachiasmatic nucleus in a Sentence

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Stepping outside briefly recalibrates the suprachiasmatic nucleus and resets alertness without a stimulant. — Allison Palmer, Charlotte Observer, 20 May 2026 Roughly six to eight hours after waking, the brain’s suprachiasmatic nucleus triggers a brief melatonin-adjacent signal that pulls your energy down, per RWJBarnabas Health. — Allison Palmer, Kansas City Star, 20 May 2026 This is done through the retinohypothalamic tract, a pathway that connects your eyes to the brain’s master body clock, called the suprachiasmatic nucleus. — Khloe Quill, FOXNews.com, 9 Nov. 2025 Our circadian rhythms, 24-hour cycles governed by the brain’s suprachiasmatic nucleus, regulate everything from body temperature to hormone release. — Ximena Araya-Fischel, Forbes.com, 12 Apr. 2025 See All Example Sentences for suprachiasmatic nucleus

Word History

First Known Use

1938, in the meaning defined above

Time Traveler
The first known use of suprachiasmatic nucleus was in 1938

Rhymes for suprachiasmatic nucleus

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supracervical
suprachiasmatic nucleus
suprachoroid
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Cite this Entry

“Suprachiasmatic nucleus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/suprachiasmatic%20nucleus. Accessed 10 Jul. 2026.

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Medical Definition

suprachiasmatic nucleus

noun
: either of a pair of neuron clusters in the hypothalamus situated directly above the optic chiasma that receive photic input from the retina via the optic nerve and that regulate the body's circadian rhythms
—abbreviation SCN
Last Updated: - Updated example sentences
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