Large animal opposite brook (5,4)

I believe the answer is:

polar bear

'large animal' is the definition.
(polar bears are large animals)

'opposite brook' is the wordplay.
'opposite' becomes 'polar' (synonyms).
'brook' becomes 'bear' (both can mean to tolerate or endure).
'polar'+'bear'='POLAR BEAR'

(Other definitions for polar bear that I've seen before include "Arctic-dwelling mammal" , "Beast of the Arctic" , "Great white animal of the Arctic" , "Arctic creature" , "Largest carnivorous land mammal" .)

I've seen this clue in The Telegraph.

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