Is over-working, at one point, in form (7)
I believe the answer is:
version
'form' is the definition.
(I know that version is a type of type)
'is over-working at one point' is the wordplay.
'working' indicates an anagram.
'at' means one lot of letters go next to another.
'one point' becomes 'n' (North).
'is'+'over'='isover'
'isover' anagrammed gives 'versio'.
'versio'+'n'='VERSION'
'in' is the link.
(Other definitions for version that I've seen before include "Rendition" , "Particular account of a matter" , "Description from a certain point of view" , "Account from one point of view" , "Sort" .)