Pronunciation: (ī-sos'tu-sē), [key]
1. Geol.the equilibrium of the earth's crust, a condition in which the forces tending to elevate balance those tending to depress.
2. the state in which pressures from every side are equal. Also,i•sos'ta•cy.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.