Annulment (noun)

1. The action of officially canceling a marriage.
2. The legal process of ending a marriage and returning both parties to the state they were in before they were married.

Origin:

Late middle english: from latin annullamentum, from annullare "cancel, make void", from ad- "to" + nullus "none".

Examples:

1. She sought an annulment of the marriage.
2. He filed for annulment on the grounds of fraud.
3. The annulment was granted and the marriage was considered null and void.
4. The annulment process can be long and difficult.
5. The annulment was granted after it was discovered that one of the parties was already married.