Brawny curs maul badly (8)
I believe the answer is:
muscular
'brawny' is the definition.
(synonyms)
'curs maul badly' is the wordplay.
'badly' indicates an anagram.
'curs'+'maul'='cursmaul'
'cursmaul' is an anagram of 'MUSCULAR'.
(Other definitions for muscular that I've seen before include "Strapping" , "Mauls cur, being well developed physically" , "Robust (sort of Christianity)" , "Brawny, hefty" , "Powerful, strong" .)