the state of clearly connecting to and mattering for the issue being discussed
文法句型
the irrelevance of [something] to [something]
treat [something] as an irrelevance in [context]
用法筆記
Most often uncountable in formal discussion, especially in patterns like 'the irrelevance of X to Y'. The countable use names a specific point that people decide can be ignored.
常見錯誤
The irrelevance of the chart for the case was obvious.
The irrelevance of the chart to the case was obvious.
When you name the matter involved, irrelevance normally takes 'to', not 'for'.