Inert gas combusts, most hot (8)

I believe the answer is:

angriest

'most hot' is the definition.

'inert gas combusts' is the wordplay.
'combusts' indicates an anagram.
'inert'+'gas'='inertgas'
'inertgas' with letters rearranged gives 'ANGRIEST'.

(Other definitions for angriest that I've seen before include "Most irate and furious" , "Most annoyed or hostile" , "Extremely mad" , "Most characteristic of 1950s young men" , "Most wrathful" .)

I've seen this clue in The Everyman puzzle in The Observer.

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