Sailor turns to playing cards (5)
I believe the answer is:
tarot
'playing cards' is the definition.
(I've seen this before)
'sailor turns to' is the wordplay.
'sailor' becomes 'tar' (slang term for a sailor).
'turns' is a reversal indicator.
'to' in reverse letter order is 'ot'.
'tar'+'ot'='TAROT'
(Other definitions for tarot that I've seen before include "Card used for fortunetelling" , "Picture card" , "Cards used for fortune telling" , "one may have been taken from deck" , "78-card pack" .)