or eu·sta·cy

[ yoo-stuh-see ]
/ ˈyu stə si /

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

1945–50; nominalization of eustatic caused by eustasy (< German eustatisch, coined by Austrian geologist Edward Suess (1831–1914); see eu-, static), with -stasy for -stasis stasis, probably on the model of ecstasy

Related forms

eu·stat·ic [yoo-stat-ik] /yuˈstæt ɪk/, adjectiveeu·stat·i·cal·ly, adverb Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for eustatic


/ (juːˈstætɪk) /


denoting or relating to worldwide changes in sea level, caused by the melting of ice sheets, movements of the ocean floor, sedimentation, etc

Derived Forms

eustasy (ˈjuːstəsɪ), nouneustatically, adverb

Word Origin for eustatic

C20: from Greek, from eu- + static
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Science definitions for eustatic


[ yōōstə-sē ]

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.

Related forms

eustatic (yōō-stătĭk)
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.