Zero in, knavishly, capturing animalistic grunt (4)
I believe the answer is:
oink
'animalistic grunt' is the definition.
'oink' can be an answer for 'grunt' (I've seen this in another clue). I am not sure about the 'animalistic' bit.
'zero in knavishly capturing' is the wordplay.
'capturing' indicates the answer is hidden within the clue (some letters captured or held by the clue).
'OINK' can be found hidden inside 'zero in knavishly'.
Can you help me to learn more?
(Other definitions for oink that I've seen before include "farmyard noise" , "Sound from a sty" , "Grunt by a pig" , "Pig's noise" , "Pig's grunt" .)