mesencephalon

noun

mes·en·ceph·a·lon ˌme-ˌzen-ˈse-fə-ˌlän

ˌmē-,

-zᵊn-,

-ˌsen-,

-sᵊn-,

-lən

: midbrain

mesencephalic

ˌme-ˌzen(t)-sə-ˈfa-lik

ˌmē-

-zᵊn(t)-

-ˌsen(t)-

-sᵊn(t)-

adjective

Word History

Etymology

New Latin

First Known Use

1846, in the meaning defined above

Time Traveler

The first known use of mesencephalon was in 1846

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mesembryanthemum

mesencephalon

mesenchymal

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Style

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

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Medical Definition

mesencephalon

noun

mes·en·ceph·a·lon ˌmez-ˌen-ˈsef-ə-ˌlän

ˌmez-ᵊn-

ˌmēz-,

ˌmēs-,

ˌmes-,

-lən

: midbrain

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mesencephalon

noun

Word History

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