eugeosyncline

noun

eu·geo·syn·cline (ˌ)yü-ˌjē-ō-ˈsin-ˌklīn

: a narrow rapidly subsiding geosyncline usually with volcanic materials mingled with clastic sediments

eugeosynclinal

(ˌ)yü-ˌjē-ō-(ˌ)sin-ˈklī-nᵊl

adjective

Word History

First Known Use

1942, in the meaning defined above

Time Traveler

The first known use of eugeosyncline was in 1942

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Browse Nearby Words

eugenol

eugeosyncline

Euglandina

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Cite this Entry

Style

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

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