Unlucky flier (4,2,3,4)

I believe the answer is:

bird of ill omen

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'unlucky flier' is the definition.
I know nothing about this answer so I cannot judge whether this works.

'unlucky flier' is the wordplay.
I cannot really see how this works, but
'unlucky' could be 'ill' (similar in meaning) and 'ill' is found in the answer.
'flier' could be 'bird' (synonyms) and 'bird' is present in the answer.
This may be the basis of the clue (or it may be nonsense).

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I've seen this clue in The Globe and Mail.

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