geo·​syn·​cline ˌjē-ō-ˈsin-ˌklīn How to pronounce geosyncline (audio)
: a great downward flexure of the earth's crust
geosynclinal adjective

Word History

First Known Use

1895, in the meaning defined above

Time Traveler
The first known use of geosyncline was in 1895

Dictionary Entries Near geosyncline

Cite this Entry

“Geosyncline.” Dictionary, Merriam-Webster, Accessed 25 Mar. 2023.

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