Clog boat’s bilge (5)
I believe the answer is:
sabot
'clog' is the definition.
(both can mean a type of shoe)
'boat's bilge' is the wordplay.
'boat's' can be anagrammed to 'SABOT'.
But, I'm not sure how this is indicated.
Can you help me to learn more?
(Other definitions for sabot that I've seen before include "Boast about wooden shoe" , "footwear from Paris" , "Wooden-soled 13 down" , "Carved shoe -- boats (anag)" , "This from last" .)