Kind of committee (2,3)
I believe the answer is:
ad hoc
'kind of committee' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for ad hoc that I've seen before include "special operation" , "(Of group) formed for one purpose only" , "(Created) for particular purpose" , "For one particular purpose" , "specific occasion" .)