What is not alterable; incapable of being altered or changed; unalterable. -- In*al"ter*a*ble*ness, n. -- In*al"ter*a*bly, adv called?

inalterable — Not alterable; incapable of being altered or changed; unalterable. -- In*al"ter*a*ble*ness, n. -- In*al"ter*a*bly, adv. (Webster's 1913.)

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