Big cat at bay? (5)

I believe the answer is:

tiger

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'big cat' is the definition.
(I know that tiger is a type of big cat)

I cannot understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for tiger that I've seen before include "Large wildcat poetically burning bright" , "The Celtic one has died" , "Fierce Bengal beast" , "Fierce person" , "Striped quadruped" .)

I've seen this clue in The Telegraph.

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