'Invalidation' definitions:

Definition of 'invalidation'

From: WordNet
noun
(law) a formal termination (of a relationship or a judicial proceeding etc) [syn: annulment, invalidation]

Definition of 'Invalidation'

From: GCIDE
  • Invalidation \In*val`i*da"tion\, n. The act of inavlidating, or the state of being invalidated. [1913 Webster]
  • So many invalidations of their right. --Burke. [1913 Webster]