Not far from Mile End (3)
I believe the answer is:
mil
'end' is the definition.
Although both the answer and definition are singular nouns, I can't understand how they can define each other.
'not far from mile' is the wordplay.
I cannot really understand how this works, but
'mile' could be 'mi' (synonyms) and 'mi' is found within the answer.
A single letter 'l' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for mil that I've seen before include "One / one thousand inch" , "tiny distance" , "One thousanth of an inch" , "One thousandth of an inch" .)