Committee men don't have a month to fill desirable job (6)
I believe the answer is:
plenum
'committee' is the definition.
(thesaurus)
'men don't have a month to fill desirable job' is the wordplay.
'don't have' indicates named letters should be taken away.
'a month' becomes 'M' (standard abbreviation).
'to fill' means one lot of letters goes inside another.
'desirable job' becomes 'plum' (I've seen this in another clue).
'men' with 'm' removed is 'en'.
'en' placed into 'plum' is 'PLENUM'.
(Other definitions for plenum that I've seen before include "Fully attended meeting" , "Meeting of whole body" , "Full assembly" , "completely filled space" , "group meeting" .)