Joker initially cut off mike (5)
I believe the answer is:
comic
'joker' is the definition.
(I've seen this in another clue)
'initially cut off mike' is the wordplay.
'initially' indicates taking the first letters.
'mike' becomes 'mic' (I've seen this in other clues).
The initial letters of 'cut off' is 'co'.
'co'+'mic'='COMIC'
(Other definitions for comic that I've seen before include "Professional joke-teller" , "Children's publication" , "Funny, droll" , "Amusing person" , "Funny entertainer, often stand-up" .)