A burning desire? (9)

I believe the answer is:

pyromania

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'a burning desire?' is the definition.
(desire to burn)

'burning desire?' is the wordplay.
'burning' becomes 'pyro' (I can't justify this - if you can you should believe this answer much more).
'desire?' becomes 'mania' (mania is a kind of desire).
'pyro'+'mania'='PYROMANIA'

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(Other definitions for pyromania that I've seen before include "Flaming madness!" , "Burning desire" , "Obsession with burning things" , "Pay Marion (anag.)" , "Criminal urge" .)

I've seen this clue in The Irish Independent and The Daily Express.

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