Confirmation (noun)

1. The action of confirming something or the state of being confirmed.
2. A ceremony or sacrament in some Christian churches by which a person is admitted as a full member.

Origin:

Late middle english: from old french, from latin confirmatio(n-), from the verb confirmare (see confirm).

Examples:

1. The confirmation of the appointment was received by email.
2. The confirmation of the flight was done at the check-in counter.
3. The confirmation of the reservation was necessary to guarantee a seat.
4. The confirmation of the order was done by phone with a credit card payment.
5. The confirmation of the youth into the church was a joyous occasion for the whole community.