The word "Wahhh" originated from the normal english word "wow". When you over use this term it can be extremely loud and annoying. For example: "WAHHHHHHHHHHHHHHHHHHHHHH..."
"Ohh he missed the net...Wahhh"
OR
"Wahhh, he just missed the net!"
(Person1): "Ohh, I just owned you!"
(Person2): "Wahhhhhhhhhhhh...."