In discussion, a directorial low point (5)
I believe the answer is:
nadir
'low point' is the definition.
(I've seen this before)
'in discussion a directorial' is the wordplay.
'in' indicates a hidden word.
'NADIR' can be found hidden inside 'discussion a directorial'.
(Other definitions for nadir that I've seen before include "worst-case scenario?" , "Lower one cannot get!" , "Low-water mark" , "Point of greatest despair" , "Low point" .)