Bad lad taken into care, possibly an occasional smoker? (7)
I believe the answer is:
caldera
'an occasional smoker?' is the definition.
(type of volcanic crater)
'bad lad taken into care possibly' is the wordplay.
'bad' indicates anagramming the letters.
'taken into' is an insertion indicator.
'possibly' is an anagram indicator.
'lad' with letters rearranged gives 'ald'.
'care' with letters rearranged gives 'cera'.
'ald' put inside 'cera' is 'CALDERA'.
(Other definitions for caldera that I've seen before include "Result of eruption" , "Big hole in rock" , "Large volcanic crater - race lad (anag)" , "Basin-shaped crater at top of volcano" , "Large volcanic crater -- lead car (anag)" .)