Leave target incomplete and veer in a different direction (2,4)
I believe the answer is:
go away
'leave' is the definition.
('go away' can be a synonym of 'leave')
'target incomplete and veer in a different direction' is the wordplay.
'target' becomes 'goal' (I've seen this before).
'incomplete' means to remove the last letter.
'and' says to put letters next to each other.
'veer' becomes 'yaw' (yawing is a kind of veering).
'in a different direction' says the letters should be written backwards.
'yaw' backwards is 'way'.
'goal' with its final letter removed is 'goa'.
'goa'+'way'='GO AWAY'
(Other definitions for go away that I've seen before include "Disappear" , "Leave" , "Scram" , "Push off" , "Depart" .)