inappeasable

in·ap·peas·a·ble

 (ĭn′ə-pē′zə-bəl)
adj.
Difficult or impossible to appease: inappeasable resentment.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

inappeasable

(ˌɪnəˈpiːzəbəl)
adj
not able to be appeased
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

in•ap•peas•a•ble

(ˌɪn əˈpi zə bəl)

adj.
not appeasable.
[1830–40]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in classic literature ?
Mr Merdle didn't want him, and was put out of countenance when the great creature looked at him; but inappeasable Society would have him--and had got him.
He seemed to project those two shining knobs of temples of his into everything that went on and to brush his hair farther and farther back, until the very roots were almost ready to fly out of his head in inappeasable philanthropy.
"Inappeasable Longings: Hawthorne, Romance, and the Disintegration of Coverdale's Self in The Blithedale Romance." The New England Quarterly, vol.
A person whose inconsistent foreign policy -- pursued with an insatiable hunger for power and short-sightedness attributable to inappeasable lust -- has made Turkey experience problems with virtually every country around the world and who was greeted with newspaper headlines reading "You are not welcome here" in Germany and Austria -- can he make a good president?
Merdle didn't want him, and was put out of countenance when the great creature looked at him; but inappeasable Society would have him--and had got him.
"Inappeasable Longings: Hawthorne, Romance and the Disintegration of Coverdale's Self in The Blithedale Romance." NEQ LXVII (1994): 257-78.