Outcry involving mollusc belonging to us (7)
I believe the answer is:
clamour
'outcry' is the definition.
(clamour is a kind of outcry)
'mollusc belonging to us' is the wordplay.
'mollusc' becomes 'clam' (clam is a kind of mollusc).
'belonging to us' becomes 'our' (us, you and me).
'clam'+'our'='CLAMOUR'
'involving' acts as a link.
(Other definitions for clamour that I've seen before include "Loud and persistent outcry" , "racket" , "Complaints" , "Loud noise of shouting" , "Din and commotion" .)