Strip off like a swimmer, on the quiet (4)
I believe the answer is:
peel
'strip off' is the definition.
(I've seen this before)
'swimmer on the quiet' is the wordplay.
'swimmer' becomes 'eel' (eels swim).
'on' says to put letters next to each other.
'the quiet' becomes 'p' (music symbol for 'piano', ie soft or quiet).
'eel' put after 'p' is 'PEEL'.
'like a' acts as a link.
(Other definitions for peel that I've seen before include "A PM; a fortified tower" , "Strip the skin off" , "Flake" , "Shed skin" , "Remove skin of vegetable or fruit" .)