Concise instruction to lawyer (5)
I believe the answer is:
brief
I believe this clue is a triple definition!
'concise' is the first definition.
(similar in meaning)
'instruction' is the second definition.
(thesaurus)
'to lawyer' is the third definition.
(I've seen this before)
(Other definitions for brief that I've seen before include "Short or concise" , "description of Macbeth's candle" , "Solicitor" , "put in the picture" , "Short - work for counsel" .)