Heavy shoe (6)
(Other definitions for boot that I've seen before include "Heavy footwear" , "Stout shoe" , "Sturdy shoe; start (a computer)" , "Profit" , "Kick; footwear" .)
'heavy shoe' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for brogan that I've seen before include "article of footwear" , "Clodhopper" .)