Officiate (verb)

1. To preside over a ceremony or event, such as a wedding or a sports game.
2. To act as an official for a ceremony or event.

Origin:

The word "officiate" comes from the latin word "officiare" which means "to perform duties".

Examples:

1. The priest officiated at the wedding.
2. The judge officiated at the trial.
3. The referee will officiate at the game.
4. The official will officiate at the ceremony.
5. The minister will officiate at the service.