He will shortly ring - for your reply (5)
I believe the answer is:
hello
'reply' is the definition.
The answer and definition can be both related to communication as well as being singular nouns.
Maybe they are linked in a way I don't understand?
'he will shortly ring for your' is the wordplay.
I cannot really understand how this works, but
'he' is present in the answer.
'will' could be 'll' (contracted form, as in 'he'll' - 'he will') and 'll' is present in the answer.
'ring' could be 'o' (letter resembling a ring) and 'o' is located in the answer.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for hello that I've seen before include "glossy magazine" , "Publication" , "Greeting - celebrity magazine" , "Look at that" , "Routine response to telephone call" .)