Policeman's description of jug? (6)
I believe the answer is:
copper
This clue might be a double definition.
'policeman's' is the first definition.
(copper can informally mean a police officer)
'description of jug?' is the second definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
Can you help me to learn more?
(Other definitions for copper that I've seen before include "Chemical element, symbol Cu" , "Small loose change" , "detector?" , "Red-brown metal" , "Metal for slang policeman" .)