diencephalon

noun

di·​en·​ceph·​a·​lon ˌdī-ən-ˈse-fə-ˌlän How to pronounce diencephalon (audio)
ˌdī-(ˌ)en-, 
-lən How to pronounce diencephalon (audio)
: the posterior subdivision of the forebrain
diencephalic
ˌdī-ən-sə-ˈfa-lik How to pronounce diencephalon (audio)
ˌdī-(ˌ)en-
adjective

Examples of diencephalon 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.
This gene is involved in brain development and is mostly expressed in a part of the brain called the diencephalon — an area previously found to differ in gay men. — Leah Froats, Discover Magazine, 7 Dec. 2017

Word History

Etymology

New Latin, from dia- + encephalon

First Known Use

circa 1883, in the meaning defined above

Time Traveler
The first known use of diencephalon was circa 1883

Rhymes for diencephalon

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Browse Nearby Words

diencephalic
diencephalon
diene
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Cite this Entry

“Diencephalon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/diencephalon. Accessed 7 Jul. 2026.

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Medical Definition

diencephalon

noun
di·​en·​ceph·​a·​lon ˌdī-ən-ˈsef-ə-ˌlän How to pronounce diencephalon (audio) ˌdī-(ˌ)en- How to pronounce diencephalon (audio)
-lən
: the posterior subdivision of the forebrain

called also betweenbrain, interbrain

diencephalic
-sə-ˈfal-ik How to pronounce diencephalon (audio)
adjective
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