Brief week in bed (6)
I believe the answer is:
lawyer
'brief' is the definition.
(slang term for a lawyer)
'week in bed' is the wordplay.
'week' becomes 'w' (abbreviation).
'in' is an insertion indicator.
'bed' becomes 'layer' (I've seen this in another clue).
'w' placed within 'layer' is 'LAWYER'.
(Other definitions for lawyer that I've seen before include "A solicitor, barrister or the like" , ""Let's kill all the --s" (Henry VI/2)" , "Legal professional" , "Man at the bar?" , "Attorney in the US" .)