Used tobacco, but was cured (6)
I believe the answer is:
smoked
'cured' is the definition.
(I've seen this before)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for smoked that I've seen before include "Dried and cured by hanging in wood vapour" , "(Of salmon) cured" , "Fumigated; cured" , "Had a cigarette" , "Cured over fire" .)