dogwatch

noun

1. Aboard a ship, either of the two short two-hour watches that take place between 4 p.m. and 8 p.m.

   “[…] in the last dog-watch when the drawing near of twilight induced revery […]”

2. (broadly)A night shift, or other very late or early period of duty.

   “The girls we knew were all on the dogwatch, from four to twelve in the morning.”

3. A very brief period of naval service.

   “At that time, Captain Thomas G. Peyton, U.S. Navy, who had only served a dog watch as Captain of the Port at Noumea, New Caledonia, reported for this important billet.”