Summary — not quite exact (6)
I believe the answer is:
precis
'summary' is the definition.
(I know that precis is a type of summary)
'not quite exact' is the wordplay.
'not quite' means to remove the last letter.
'exact' becomes 'precise' (associated in meaning).
'precise' with its final letter removed is 'PRECIS'.
(Other definitions for precis that I've seen before include "Prices for a summary" , "Summarize" , "Synopsis, summary" , "Prices for abbreviated version" , "Summary of the main points" .)