There are multiple definitions - click on the translation that matches your context.

annullering

substantiv

full

annulment

noun

Definitions of annulment

an official declaration by a court that a marriage is void (=has no legal authority and is therefore not valid)

She wanted an annulment after four years of marriage.

the act of making something void (=declaring that it has no legal authority and is therefore not valid)

The US initially appeared to support the annulment of the election.