Expand distribution of boots (5)
I believe the answer is:
boost
'expand' is the definition.
(thesaurus)
'distribution of boots' is the wordplay.
'distribution of' indicates an anagram.
'boots' anagrammed gives 'BOOST'.
(Other definitions for boost that I've seen before include "Improve - pick-me-up" , "Push upwards, help" , "Recharge" , "Shot in the arm" , "Raise" .)