unalterable

/ˈʌnˌɔltərəbəl/

You take your dress to the tailor to be altered. He tells you he can't alter it. The dress is unalterable. Something unalterable cannot be changed.

Take the prefix un-, meaning "not". Add it to the word alter, meaning "change." Tack on the suffix -able, meaning "possible." The result? Unalterable, "impossible to change." The things you've done in the past are unalterable. The only things you have the power to change are the things you're doing right now or that you will do in the future. How can you alter things that haven't happened yet? Good question. For all we know, they're unalterable too.

Definitions of unalterable

1. adjective

   not capable of being changed or altered
   “unalterable resolve”

   “an unalterable ground rule”

   synonyms: inalterable

   incurable

   unalterable in disposition or habits

   final, last

   not to be altered or undone

   antonyms:

   alterable

   capable of being changed or altered in some characteristic
2. adjective

   of a sentence; that cannot be changed
   synonyms:

   incommutable

   not subject to alteration or change
3. adjective

   remaining the same for indefinitely long times
   synonyms: changeless

   unchangeable

   not changeable or subject to change