unalterability
1. [ noun ] the quality of not being alterable
Related terms: alterability immutability incurability
2. [ noun ] the quality of being fixed and unchangeable
Synonyms: fixedness
Examples:

"the fixedness of his gaze upset her"

Related terms: changelessness
Similar spelling:   unalterably
  unalterable
  unilaterally
  unilateralist
  unilateralism