encephalon

noun

en·ceph·a·lon in-ˈse-fə-ˌlän

-lən

plural encephala in-ˈse-fə-lə

: the vertebrate brain

Word History

Etymology

New Latin, from Greek enkephalos

First Known Use

1741, in the meaning defined above

Time Traveler

The first known use of encephalon was in 1741

See more words from the same year

Cite this Entry

Style

“Encephalon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/encephalon. Accessed 4 Nov. 2025.

Copy Citation

Medical Definition

encephalon

noun

en·ceph·a·lon in-ˈsef-ə-ˌlän

-lən

plural encephala -lə

: the vertebrate brain

More from Merriam-Webster

Word of the Day

spontaneous

Listen to the pronunciation of spontaneous

See Definitions and Examples »

Get Word of the Day daily email!

Popular in Grammar & Usage

'Affect' vs. 'Effect'

Using Bullet Points ( • )

The Difference Between 'i.e.' and 'e.g.'

What’s the difference between ‘cemetery’ and ‘graveyard’?

Democracy or Republic: What's the difference?

Popular in Wordplay

Skibidi, Mog & More: Gen Alpha Slang

13 Wonderful Words That You're Not Using (Yet)

Ten More Words from Taylor Swift Songs

Birds Say the Darndest Things

Even More Bird Names that Sound Like Insults (and Sometimes Are)

Popular

'Affect' vs. 'Effect'

Skibidi, Mog & More: Gen Alpha Slang

13 Wonderful Words That You're Not Using (Yet)