Sailor in drunk's wooden shoe (5)
I believe the answer is:
sabot
'wooden shoe' is the definition.
(I've seen this before)
'sailor in drunk's' is the wordplay.
'sailor' becomes 'ab' (abbreviation for able seaman).
'in' indicates putting letters inside.
'drunk' becomes 'sot' (both can mean someone who drinks too much).
'ab' going inside 'sot' is 'SABOT'.
(Other definitions for sabot that I've seen before include "This from last" , "footwear from Paris" , "French clog" , "Wooden clog" , "what's afoot?" .)