One shot in leg undeterred (3)

I believe the answer is:

gun

'one shot' is the definition.
(thesaurus)

'in leg undeterred' is the wordplay.
'in' indicates the answer is hidden within the clue.
'GUN' is hidden within 'leg undeterred'.

(Other definitions for gun that I've seen before include "Firearm" , "Hand weapon" , "Rev up" , "Arm" , "Shooter" .)

I've seen this clue in The Times.

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