Voice disapproval of Best's last kick (4)
I believe the answer is:
boot
'kick' is the definition.
(synonyms)
'voice disapproval of best's last' is the wordplay.
I cannot really see how this works, but
'disapproval' could be 'boo' (as in a crowd booing) and 'boo' is found in the answer.
'last' could be 't' (I've seen this in other clues) and 't' is present in the answer.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for boot that I've seen before include "eg Wellington" , "Profit" , "Clothing; kick" , "Car luggage space; kick" , "Item of footwear" .)