Litter depository? (7)
I believe the answer is:
piggery
'litter depository?' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Maybe there's a link between them I don't understand?
'litter depository?' is the wordplay.
'litter' becomes 'pig' (pigging is a kind of littering).
'depository?' becomes 'gery' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'pig'+'gery'='PIGGERY'
Can you help me to learn more?
(Other definitions for piggery that I've seen before include "Enclosure for boars and sows" , "Sty" , "Farm producing pork" .)