The loud volume of voice that teachers use. It's not really a yell since that indicates fear or anger--just the loud, obnoxious voice of someone
accustomed to endeavouring to
speak over the crowd without sounding angry. Off-duty teachers often don't know they are being
too loud and coming off as bossy.
"If you're getting up, would you bring me
a glass of water?"
"
Stop shouting,
I'm right next to you. You've been shouting since you got here."
"Sorry, it's my teacher voice."
