A word used in fustration, boredom or as a sign of indifference. It is similar to a goat sound.
Example 1:
Tim: "What movie do you want to watch, babe?"
Sally: "Merrr."
Example 2:
Mom: "Wash the dishes."
Child: "MERRR."
Example 3:
Alice: "Isn't this a great movie?"
Sam: "Merrr."