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Do you mean a Sarcasm Failure sort of thing or throat infection/injury sort of thing?
The latter.
That's The Speechless (which is for general physical inability to speak).
I think OP was asking if there was a trope about the smarmy, chatty character temporarily losing the ability to speak, and has to spend an episode without making jokes.
Isn't The Speechless about full-time mute characters?
Oo oo ah ah
Not necessarily, it has examples of temporarily mute characters. Dumb Struck doesn't work, because it's not physical, so - no more ideas from me.
ETA: Well, maybe Sick Episode, but this is very general.
Edited by Veanne
There's Lost Voice Plot for when the plot revolves around any character losing their voice for one reason or another.
I'm just a psycho, babe! Come and go out my mind. I didn't lose it, babe! There wasn't much to find.
Okay, how did you find it? My searching technique can obviously use refining.
A character who snarks a lot or makes jokes can't speak for an episode.