Comedian has a delay (4)
I believe the answer is:
wait
'delay' is the definition.
(I know that delay is a more specific form of the action the wait)
'comedian has a' is the wordplay.
'comedian' becomes 'wit' (a witty person).
'has' is an insertion indicator.
'wit' enclosing 'a' is 'WAIT'.
(Other definitions for wait that I've seen before include "Cool one's heels" , "Linger, delay" , "Hold on" , "Attend, expect" , "Be patient" .)