shiftwork

Short definition from Wiktionary

Noun

1. 1
   Scheduled work outside of customary daylight working hours.
2. 2
   A mode of employment in which sets of workers are rotated to maintain a continuous 24/7 operation; usually, with a system of three 8-hour shifts (24 ÷ 3 = 8): first shift, second shift, and third shift.