nonconformity

noun | \ ˌnän-kən-ˈfȯr-mə-tē \ | non·con·for·mi·ty

1. : failure to conform to or comply with something (as contract requirements) a lessee may revoke acceptance of a lot…whose nonconformity substantially impairs its value —Uniform Commercial Code

2. : a particular aspect in which something is nonconforming cannot revoke an acceptance he made with knowledge of a nonconformity —J. J. White and R. S. Summers