Definitions
1.AdjectiveNot relevant, as:"His comments were completely irrelevant to the discussion.; We need to focus on the main topic and ignore irrelevant details.; The fact that she is his sister is irrelevant to the case."
2.AdjectiveNot at all related: totally unrelated, wholly unconnected, completely inapplicable.
3.AdjectiveNot usefully related: not associated in any way that is important or useful to the context being discussed: not materially applicable; having connections not applicable in the present situation.
4.AdjectiveNo longer famous or popular; washed up.