Bird, chicken, not caught (5)

I believe the answer is:

raven

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'bird' is the definition.
(raven is a kind of bird)

I cannot understand how the remainder of the clue works.

(Other definitions for raven that I've seen before include "Bird in 1's poem" , "Species of crow" , "Bird of ill omen" , "Glossy black colour" , "Type of crow" .)

I've seen this clue in The Telegraph and The Guardian.

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