Mouthy old dons judge addressed in court (4)
I believe the answer is:
loud
'mouthy' is the definition.
(I've seen this in another clue)
'old dons judge addressed in court' is the wordplay.
I cannot quite understand how this works, but
'old' could be 'o' (common abbreviation eg in OE for Old English) and 'o' is located in the answer.
'judge' could be 'lud' (I've seen this in other clues) and 'lud' is present in the remaining letters.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for loud that I've seen before include "vulgar" , "Audibly, or visually, obtrusive" , "strongly audible" , "Tasteless; of great volume" , "Noisily showy?" .)