Unimportant, insignificant, or not relevant to a particular matter. Something that has no notable influence or consequences.
example
Ob wir fünf Minuten früher oder später ankommen, ist unerheblich.
Whether we arrive five minutes earlier or later is irrelevant.
Usage tips
Word structure
The word is made up of the negation 'un-' and the adjective 'erheblich' (significant/considerable). 'Erheblich' means 'significant' or 'considerable', so 'unerheblich' (irrelevant/insignificant) literally means 'not significant'.
EXAMPLE
Der finanzielle Schaden war zum Glück unerheblich.
Fortunately, the financial damage was insignificant.
Formal style
'Unerheblich' (irrelevant/insignificant) is a word used mainly in written language, formal discussions, or official contexts. It sounds more elevated than everyday expressions.
EXAMPLE
Für den Ausgang des Verfahrens sind diese Details unerheblich.
These details are irrelevant to the outcome of the proceedings.
Sentence structure with subordinate clauses
'Unerheblich' (irrelevant) is very often used in the structure 'Es ist unerheblich, ob/wer/was/wie ...' (It is irrelevant whether/who/what/how ...), followed by a subordinate clause. This expresses that a particular question or condition does not matter.
EXAMPLE
Es ist unerheblich, wer den Fehler gemacht hat; wichtig ist, dass wir ihn beheben.
It is irrelevant who made the mistake; what matters is that we fix it.
Compare with
antonym
unerheblich vs wichtig
important
'wichtig' and 'unerheblich' are opposites. Use 'wichtig' when something matters or can have consequences. 'unerheblich' means that something does not matter for a particular issue or has no influence. 'unerheblich' sounds somewhat more formal than 'unwichtig' and fits well in factual discussions, for example about rules, contracts, or decisions.
unerheblich
Für die Anmeldung ist es unerheblich, ob du den Kurs schon einmal besucht hast.
For registration, it is irrelevant whether you have taken the course before.
wichtig
Nach der Arbeit ist ihr die Zeit mit den Kindern besonders wichtig.
After work, time with her children is especially important to her.