Burning a type of engine (10)

I believe the answer is:

combustion

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'burning' is the definition.
(I know that burning can be written as combustion)

'a type of engine' is the wordplay.
'a type of' becomes 'combust' (I can't justify this - if you can you should give a lot more credence to this answer).
'engine' becomes 'ion engine' (ion engine is a kind of engine).
'combust'+'ion'='COMBUSTION'

Can you help me to learn more?

(Other definitions for combustion that I've seen before include "See 12 and 20" , "Process of burning" .)

I've seen this clue in The Daily Express.

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