How a dog can keep a monarch out (7)
I believe the answer is:
barking
'how a dog can keep a' is the definition.
I can't tell whether this definition defines the answer.
'monarch out' is the wordplay.
I cannot quite understand how this works, but
'monarch' could be 'king' (king is a kind of monarch) and 'king' is present in the answer.
The remaining letters 'bar' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for barking that I've seen before include "What Battersea resident may be doing" , "Mad - town forming a London borough with Dagenham" , "Area of London - mad?" , "Mental" , "Dog may be" .)