A nominal figure (5)
I believe the answer is:
oscar
'a nominal figure' is the definition.
The answer and definition can be both related to communication as well as being singular nouns.
Maybe you can see a link between them that I can't see?
This is all the clue.
Can you help me to learn more?
(Other definitions for oscar that I've seen before include "Award by the Academy of Motion Picture Arts and Sciences" , "Code word for O" , "academy's prize" , "Film industry award" , "- - Hammerstein (musicals)" .)