verb, -at⋅ed, -at⋅ing.| 1. | to perform the office of a member of the clergy, as at a divine service. |
| 2. | to perform the duties or function of some office or position. |
| 3. | to serve as referee, umpire, or other official in a sports contest or game. |
| 4. | to serve as the priest or minister of (a divine service, religious ceremony, etc.). |
| 5. | to perform, carry out, or fulfill (an official duty or function). |
| 6. | to act as a referee, umpire, timekeeper, or other official for (a sports contest or game). |