Thug loves the curse (6)
I believe the answer is:
hoodoo
'the curse' is the definition.
(thesaurus)
'thug loves' is the wordplay.
'thug' becomes 'hood' (synonyms).
'loves' becomes 'oo' (two O's - 'love' means zero in tennis).
'hood'+'oo'='HOODOO'
(Other definitions for hoodoo that I've seen before include "Thing or person thought to cause bad luck" , "Jinx" , "Spells" , "Witchcraft" , "Bringer of bad luck" .)