Irrelevant vs. Irrelative — What's the Difference?

Unrelated to the matter being considered.

Having no correlative relationship; unconnected.

Not relevant, as:

Irrelevant.

Not at all related: totally unrelated, wholly unconnected, completely inapplicable.

Having no relations to each other; unrelated.

Not 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.

Not related to the subject at hand; irrelevant.

Having no bearing on or connection with the subject at issue;

(music) Describing two or more chords which do not share any notes in common.

Not relative; without mutual relations; unconnected.