noun, plural eu·sta·sies. Geology.
any uniformly global change of sea level that may reflect a change in the quantity of water in the ocean, or a change in the shape and capacity of the ocean basins.
Origin of eustasy
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
A uniform worldwide change in sea level caused especially by fluctuations in the amount of water taken up by continental and polar icecaps, or by a change in the capacity of ocean basins.
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