coeternal

adjective

co·​eter·​nal ˌkō-i-ˈtər-nᵊl How to pronounce coeternal (audio)
: equally or jointly eternal
… the old 19th-century view that … if life and matter are coeternal, there is no problem of the origin of life to be figured out.—Carl Sagan
coeternally adverb
existing coeternally
coeternity
ˌkō-i-ˈtər-nə-tē How to pronounce coeternal (audio)
noun

Word History

Etymology

Middle English, borrowed from Late Latin coaeternālis, from Latin co- co- + Late Latin aeternālis eternal entry 1, after coaeternus "coeternal"

First Known Use

14th century, in the meaning defined above

Time Traveler
The first known use of coeternal was in the 14th century

Rhymes for coeternal

See All Rhymes for coeternal

Browse Nearby Words

coeteris paribus
coeternal
Coetzee
See all Nearby Words

Cite this Entry

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

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