annulment

Short definition from Wiktionary

Noun

1. 1
   An act or instance of annulling.
2. 2
   The state of having been annulled.
3. 3
   An invalidation of something, especially a legal contract.
4. 4
   A legal (notably judicial) declaration that a marriage is invalid; the procedure leading to it.
5. 5
   Total destruction.