Go half a mile, just a short way (5)
I believe the answer is:
leave
'go half' is the definition.
'leave' can be an answer for 'go' (leaving is a kind of going). I am not certain of the 'half' bit.
'a mile just a short way' is the wordplay.
'a mile just' becomes 'le' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'a short way' becomes 'ave' (abbreviation for avenue, a type of 'way'; 'short' indicates an abbreviation).
'le'+'ave'='LEAVE'
Can you help me to learn more?
(Other definitions for leave that I've seen before include "Permission - depart" , "Permission to take a vacation" , "Depart - on office holidays?" , "Skip" , "Pull out" .)