Bum ciggy, ultimately nick matches for smoker? (7,5)

I believe the answer is:

chimney stack

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'smoker?' is the definition.
Both the definition and answer are singular nouns.
Maybe they are linked in a way I don't understand?

'bum ciggy ultimately nick matches' is the wordplay.
'bum' indicates anagramming the letters (bum can mean faulty or wrong).
'ultimately' says to take the final letters.
The final letter of 'ciggy' is 'y'.
'y'+'nick'+'matches'='ynickmatches'
'ynickmatches' with letters rearranged gives 'CHIMNEY-STACK'.

'for' acts as a link.

Can you help me to learn more?

(Another definition for chimney stack that I've seen is " Roof flue structure".)

I've seen this clue in The Guardian.

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