myelencephalon

noun

my·​e·​len·​ceph·​a·​lon ˌmī-ə-len-ˈse-fə-ˌlän How to pronounce myelencephalon (audio)
-lən-
: the posterior part of the developing vertebrate hindbrain or the corresponding part of the adult brain composed of the medulla oblongata
myelencephalic
ˌmī-ə-ˌlen(t)-sə-ˈfa-lik How to pronounce myelencephalon (audio)
adjective

Word History

Etymology

earlier, as a name for the cerebrospinal axis of vertebrates, from myel- + encephalon, perhaps after French myélencéphale

First Known Use

1871, in the meaning defined above

Time Traveler
The first known use of myelencephalon was in 1871

Rhymes for myelencephalon

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Browse Nearby Words

mydriasis
myelencephalon
-myelia
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Cite this Entry

“Myelencephalon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/myelencephalon. Accessed 3 Nov. 2025.

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Medical Definition

myelencephalon

noun
my·​el·​en·​ceph·​a·​lon ˌmī-ə-len-ˈsef-ə-ˌlän, -lən How to pronounce myelencephalon (audio)
: the posterior part of the developing vertebrate hindbrain or the corresponding part of the adult brain composed of the medulla oblongata
myelencephalic
-ˌlen(t)-sə-ˈfal-ik How to pronounce myelencephalon (audio)
adjective

More from Merriam-Webster on myelencephalon

Britannica.com: Encyclopedia article about myelencephalon

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