Vocalist's assistant (4)
I believe the answer is:
mike
'vocalist's assistant' is the definition.
Although both the answer and definition are singular nouns, I don't understand how they can define each other.
This is the entire clue.
Can you help me to learn more?
(Other definitions for mike that I've seen before include "Boy's name - November's predecessor" , "megaphone" , "letter in code" , "Boy's name; piece of recording equipment" , "T [Thespian] Reid" .)