Instinct finds target, missing a beat (7)
I believe the answer is:
impulse
'instinct' is the definition.
(thesaurus)
'target missing a beat' is the wordplay.
'target' becomes 'aim' (both can mean a goal or purpose).
'missing' indicates named letters should be taken away.
'beat' becomes 'pulse' (pulsing is a kind of beating).
'aim' with 'a' taken away is 'im'.
'im'+'pulse'='IMPULSE'
'finds' is the link.
(Other definitions for impulse that I've seen before include "Sudden urge to act" , "Drive" , "Instinctive motive" , "Chew" , "Maybe unthinking urge" .)