Long and short of it (4)
I believe the answer is:
gist
'long and short of it' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for gist that I've seen before include "Central meaning or theme" , "Main idea, kernel of matter" , "The essential point of something" , "Main point of the matter" , "The substance of a text" .)