'non-issue' definitions:

Definition of 'non-issue'

(from WordNet)
noun
The state of something that has outlived its relevance [syn: dead letter, non-issue]

Definition of 'non-issue'

From: GCIDE
  • non-issue \non-issue\ n. the state of something that has outlived its relevance.
  • Syn: dead letter. [WordNet 1.5]