Booth charge for horse (8)
I believe the answer is:
stallion
'horse' is the definition.
(thesaurus)
'booth charge' is the wordplay.
'booth' becomes 'stall' ('stall' can be a synonym of 'booth').
'charge' becomes 'ion' (an ion is a charged particle).
'stall'+'ion'='STALLION'
'for' is the link.
(Other definitions for stallion that I've seen before include "Stud" , "Male horse kept for breeding" , "Mount" , "Male steed" , "Mare's mate" .)