Skins turned up to show the nap (5)
I believe the answer is:
sleep
'the nap' is the definition.
(synonyms)
'skins turned up' is the wordplay.
'skins' becomes 'peels' ('peel' can be a synonym of 'skin').
'turned up' is a reversal indicator.
'peels' back-to-front is 'SLEEP'.
'to show' is the link.
(Other definitions for sleep that I've seen before include "Doze, nap" , "Slumber" , "Be dormant" , "crash" , "''... that knits up the ravell'd sleeve of care'' (Macbeth)" .)