Interior coverings for ships (6)
I believe the answer is:
liners
'for ships' is the definition.
(liner is a kind of ship)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for liners that I've seen before include "craft?" , "Large commercial ships" , "Large ocean-going ships" , "These go inside" , "cruise ships" .)