After month, spreading bile makes some noise (7)
I believe the answer is:
decibel
'some noise' is the definition.
(I've seen this before)
'after month spreading bile' is the wordplay.
'after' says to put letters next to each other.
'month' becomes 'dec' (abbreviation for December).
'spreading' is an anagram indicator.
'bile' with letters rearranged gives 'ibel'.
'dec' put next to 'ibel' is 'DECIBEL'.
'makes' acts as a link.
(Other definitions for decibel that I've seen before include "Sound level unit" , "Level of noise" , "Unit relating to sound or power measurement" , "Unit of volume" , "I relate to volume" .)