Starts fire using expired laughing gas! (4)

I believe the answer is:

fuel

'gas' is the definition.
(I've seen this in another clue)

'starts fire using expired laughing' is the wordplay.
'starts' says to take the initial letters.
The initial letters of 'fire using expired laughing' is 'FUEL'.

(Other definitions for fuel that I've seen before include "Eg, coal or petrol" , "Burned source of energy" , "Substance burned to source power" , "Combustible material" , "coal etc" .)

I've seen this clue in The Irish Times.

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