Incapable of being modified; immune to modification.(adjective)
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Use "unmodifiable" in a sentence
"It's also worth remembering that this "unmodifiable" pro-capitalist human nature, far from being inherent in the human character, defies the historical record."
"My preferred model for health insurance is that premiums should be increased when persons have modifiable risk factors (such as tobacco use, sedentary lifestyle, or untreated hypertension) but not for unmodifiable risks (such as family history of heart disease or genetic propensity for tumors)."
"By your logic, the Philadelphia Convention of 1787 was UnArticles-of-Confederational and George Washington should have arrested and exiled Franklin, Madison and the lot of them for treason in seeking to modify a document that declares itself unmodifiable."