The answer to a bit of a black eye? (3)
I believe the answer is:
key
'the answer' is the definition.
The definition and answer can be both related to communication as well as being singular nouns.
Maybe you can see a link between them that I don't see?
'bit of a black eye?' is the wordplay.
'bit of' indicates the answer is hidden within the clue.
'KEY' can be found hidden inside 'black eye'.
'to a' acts as a link.
Can you help me to learn more?
(Other definitions for key that I've seen before include "It opens the door" , "Of crucial importance" , "Eg, Ctrl, Alt or Esc" , "Coral reef off southern coast of Florida" , "//www.crosswordgiant.com/crossword-clue/1252911/" .)