Fadiddledoingdoing.
What you say when the silence is so loud it's like your brain is screaming.
'Fadiddledoingdoing,' he said, because the silence was a scream in disguise.
'Fadiddledoingdoing,' she said, because the silence was a loud whisper.
'Fadiddledoingdoing,' they both said, because the silence was a scream with no sound.