In Diné (Navajo) culture it is an
expression used to acknowledge something in
disappointment and/or apathy, or even in a comedic
condescending way.
It can be prolonged to “wahhh” depending on context and how the user decides to use.
Rez dude - “Hey
did you hear your uncle so-and-so
picked up a new ride?”
Rez chick - “No huh uh, what did he get?”
Rez dude - “don’t even know, it’s
an old used truck.”
Rez chick - “Wahhh”