Herald features final letter from Greece (5)
I believe the answer is:
omega
This might be a double definition.
'herald features final' is the first definition.
The definition and answer can be both related to communication as well as being singular nouns.
Perhaps there's a link between them I don't understand?
'letter from greece' is the second definition.
(letter from the Greek alphabet)
Can you help me to learn more?
(Other definitions for omega that I've seen before include "Final outcome" , "Greek finalist" , "symbol of resistance?" , "letter from abroad" , "24th Greek letter" .)