Irrevocableness is a noun that means the quality of being irreversible or unable to be undone. When describing such a situation, one could use words like finality, permanence, or conclusiveness. If something is unalterable and resolute, then it is also irrevocable. Similarly, words such as unwavering, unchangeable, and immutable can also be used to describe the state of something being irrevocable. Another synonym that can be used to describe a situation where a decision cannot be changed is irrefutable, which suggests that there is no doubt or argument that can be made against it. Ultimately, all of these words reflect a permanent state that cannot be undone.