My kids have been saying, "ROAR!" a lot lately. It's so cute and really does convey their feelings on life, my parenting, their sibling and things in general.
Here is an example of it's usage.
Setting: 6 am any weekday morning.
"Time to get up Poopy-butt." I lovingly* say.
"Mumble, garble." B responds.
"No, really it's time to get up, Stinky Feet. Get up. Get up." I gently* encourage.
"ROAR!" she growls as she flips over and cracks an eye at me.
"Wakey-wakey, eggs and bakey." I sweetly* sing.
"No, ROAR! I don't want to get up!!"
(*loving, gentle, and sweetly are used in replace of harried, frustrated, and annoyed in this context)