Torch a log enriched with nuclear iodine, say (7)
I believe the answer is:
halogen
'iodine say' is the definition.
(I know that I is a type of halogen)
'torch a log enriched with' is the wordplay.
'with' indicates the answer is hidden within the clue.
'HALOGEN' is hidden within 'torch a log enriched'.
'nuclear' is the link.
This may not be correct. It may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for halogen that I've seen before include "Chlorine, fluorine, bromine, iodine or astatine?" , "I must be regarded as one" , "reactive group member" , "Eg, fluorine or chlorine" , "I too maybe" .)