Bad lad in south is bizarre (10)
I believe the answer is:
outlandish
'bizarre' is the definition.
(synonyms)
'bad lad in south' is the wordplay.
'bad' is an anagram indicator.
'lad'+'in'+'south'='ladinsouth'
'ladinsouth' anagrammed gives 'OUTLANDISH'.
'is' is the link.
(Other definitions for outlandish that I've seen before include "Exotic" , "Bizarre - hound's tail (anag)" , "Lad shoutin' (anag)" .)