Northern Irish donkey brays harshly in this manner, perhaps. (5)
I believe the answer is:
nasal
This clue could be a double definition.
'northern irish' is the first definition.
The answer and definition can be both related to communication as well as being singular nouns.
Maybe you can see an association between them that I don't see?
'donkey brays harshly in this manner perhaps' is the second definition.
Although both the answer and definition are singular nouns, I can't understand how they can define each other.
Can you help me to learn more?
(Other definitions for nasal that I've seen before include "nozzle" , "regarding the nose" , "Hooters" , "Concerning the nose" , "To do with nose, say sound" .)