Animal of the most agile kind? (4)

I believe the answer is:

stag

'animal' is the definition.
(stag is a kind of animal)

'of the most agile kind?' is the wordplay.
'of' indicates a hidden word.
'STAG' can be found hidden inside 'most agile kind'.

(Other definitions for stag that I've seen before include "Excluding women" , "Male-only" , "One who speculates" , "Share speculator" , "Investor" .)

I've seen this clue in the Evening Standard.

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