It's in an arable area (3)
I believe the answer is:
lea
'area' is the definition.
(lea is a kind of area)
'it's in an arable' is the wordplay.
'it' becomes 'e' ('e' can mean 'electronic' which is similar to 'IT').
'in' means one lot of letters goes inside another.
'an arable' becomes 'la' (I can't explain this - if you can you should give a lot more credence to this answer).
'e' inserted into 'la' is 'LEA'.
Can you help me to learn more?
(Other definitions for lea that I've seen before include "Open arable land (poet.)" , "Land growing grass" , "River of east London" , "Tract of pastureland" , "Field" .)