Silenced, or made a joke (6)
I believe the answer is:
gagged
'silenced' is the definition.
(gagging is a kind of silencing)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for gagged that I've seen before include "Not allowed to speak out" , "Silenced" , "Struggled for breath or prevented from speaking out" , "Muffled or retched" .)