1. n. [Drilling]

The work shift of a drilling crew that starts in the evening or late afternoon. Drilling operations usually occur around the clock because of the cost to rent a rig. As a result, there are usually two separate crews working twelve-hour tours to keep the operation going. Some companies prefer three eight-hour tours: the evening tour starts at 4 PM; the graveyard tour is the overnight shift or the shift that begins at midnight. (Pronounced "tower" in many areas.)

Antonyms: morning tour

See: tour