Swab the deck (3)
I believe the answer is:
mop
'swab the deck' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for mop that I've seen before include "Mass of disordered hair" , "It's used to wipe the floor" , "Wet cleaner" , "Polish" , "Instrument for cleaning" .)