Bunks on a ship (6)
I believe the answer is:
berths
'bunks on a ship' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for berths that I've seen before include "Beds on ships or trains" , "Spaces in port for ships and boats" , "Beds on boats" , "Docks" , "Beds on ship or train" .)