Definition of bunks:
(n) :
One of a series of berths or beds placed in tiers.
(n) :
(nautical) A built-in bed on board ship, often erected in tiers one above the other.
(n) :
(military) A cot.
(n) :
(US) A wooden case or box, which serves for a seat in the daytime and for a bed at night.
(n) :
(US, dialect) A piece of wood placed on a lumberman's sled to sustain the end of heavy timbers.
(n) :
(Singapore, military, by extension) A dormitory or bunkroom where soldiers sleep.