Dire commercial jingle (7)

I believe the answer is:

adverse

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'dire' is the definition.
(I've seen this before)

'commercial jingle' is the wordplay.
'commercial' becomes 'ad' (abbreviation for advertisement).
'jingle' becomes 'verse' (I can't explain this - if you can you should believe this answer much more).
'ad'+'verse'='ADVERSE'

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(Other definitions for adverse that I've seen before include "negative result" , "Contrary -- inauspicious" , "Unfavourable - red vase (anag)" , "Hostile" , "'Unfavourable, contrary (7)'" .)

I've seen this clue in The Telegraph.

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