Bird seed with smoother coating (9)
I believe the answer is:
sandpiper
'bird' is the definition.
(sandpiper is a kind of bird)
'seed with smoother coating' is the wordplay.
I cannot quite see how this works, but
'seed' could be 'pip' (I've seen this before) and 'pip' is located in the answer.
'with' could be 'and' and 'and' is found in the answer.
This explanation may well be incorrect...
(Other definitions for sandpiper that I've seen before include "Shore bird" , "Shorebird found on sniper pad" , "Ground-dwelling wading bird" , "Coastal wading bird" , "knot" .)