Train niece in treatment for burn (10)

I believe the answer is:

incinerate

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'burn' is the definition.
(synonyms)

'train niece in treatment' is the wordplay.
'train niece' anagrams to 'INCINERATE'.
Though, I am unsure how the anagram is indicated.

'for' is the link.

Can you help me to learn more?

(Other definitions for incinerate that I've seen before include "Reduce to ashes" , "Fierily destroy" , "Completely burn" , "Destroy by burning" , "Reduce to ash" .)

I've seen this clue in The Daily Express.

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