Competitor not very taken aback? Retreat (4)

I believe the answer is:

lair

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'retreat' is the definition.
(both can mean a private hideout)

I cannot understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for lair that I've seen before include "Rail around animal's den" , "A nautical hail" , "animal refuge" , "Wild animal's place of refuge" , "Waylay" .)

I've seen this clue in The Independent.

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