Bar admitting final section of lawyer's citation (7)
I believe the answer is:
excerpt
'lawyer's citation' is the definition.
'excerpt' can be an answer for 'citation' (thesaurus). I'm not sure about the 'lawyer's' bit.
'bar admitting final section' is the wordplay.
'bar' becomes 'except' (both can mean 'not including').
'admitting' is an insertion indicator (admit can mean to welcome in or accept).
'final section' becomes 'r' (I can't justify this - if you can you should believe this answer much more).
'except' enclosing 'r' is 'EXCERPT'.
'of' acts as a link.
Can you help me to learn more?
(Other definitions for excerpt that I've seen before include "Just a few words" , "scrap?" , "newspaper clipping" , "part of programme" , "Piece selected from a film" .)