When dogs go to earth, it means trouble (5)
I believe the answer is:
curse
'trouble' is the definition.
(I know that curse is a type of affliction)
'when dogs go to earth' is the wordplay.
I cannot really see how this works, but
'dogs' could be 'curs' (cur can mean a violent dog) and 'curs' is located in the answer.
'earth' could be 'e' and 'e' is found in the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
'it means' is the link.
Can you help me to learn more?
(Other definitions for curse that I've seen before include "Imprecation or oath" , "Imprecate" , "Execration" , "It's bad spelling" , "Utter obscenities" .)