1
: general equilibrium in the earth's crust maintained by a yielding flow of rock material beneath the surface under gravitative stress
2
: the quality or state of being subjected to equal pressure from every side

Word History

Etymology

International Scientific Vocabulary is- + Greek -stasia condition of standing, from histanai to cause to stand — more at stand

First Known Use

1889, in the meaning defined at sense 1

Time Traveler
The first known use of isostasy was in 1889

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Cite this Entry

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

Kids Definition

: the state of balance that exists between the earth's crust and the denser rock material beneath

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