To see a short distance is not difficult (5)
I believe the answer is:
cinch
'to see' is the definition.
(cinching is a kind of seeing)
'a short distance is not difficult' is the wordplay.
'a short' means to remove the last letter.
'distance' becomes 'cm'.
'is not difficult' becomes 'inch' (I can't justify this - if you can you should believe this answer much more).
'cm' with its last letter removed is 'c'.
'c'+'inch'='CINCH'
Can you help me to learn more?
(Other definitions for cinch that I've seen before include "piece of cake" , "simple job" , "Doddle" , "Something easily done" , "A walk in the park" .)