He doesn't appreciate where the coal goes (7)
I believe the answer is:
ingrate
This clue could be a double definition.
'he doesn't appreciate' is the first definition.
(I've seen this before)
'where the coal goes' 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 ingrate that I've seen before include "No thanks, I say!" , "He doesn't appreciate" , "Churlish type" , "One who never says thanks" , "Unappreciative person" .)