G.T.I.Y.
A bad habit that people use to shut down anyone who's being too loud or too quiet.
My brother yelled at the teacher for 10 minutes. I told him G. T. I. Y. and he sat down.
My sister was too quiet to talk. I said G. T. I. Y. and she started screaming.
My friend was too loud at the dinner table. I told him G. T. I. Y. and he shut up.