Little spot outside Leatherhead (6)
I believe the answer is:
slight
'little' is the definition.
(I know that little can be written as slight)
'spot outside leatherhead' is the wordplay.
'spot' becomes 'sight' (both can mean to notice or observe).
'outside' is an insertion indicator.
'leatherhead' becomes 'l' (head letter of 'leather').
'sight' enclosing 'l' is 'SLIGHT'.
(Other definitions for slight that I've seen before include "Insult - not important!" , "Flimsy, tenuous" , "Deliberate discourteous act" , "Minor -- snub" , "Put down" .)