Large amount in pails (7)
I believe the answer is:
buckets
This clue is a double definition.
'large amount' is the first definition.
'pails' is the second definition.
('bucket' can be a synonym of 'pail')
'in' is the link.
(Other definitions for buckets that I've seen before include "Pails" , "castle-builders!" , "Loads" .)