yeenhaw

"Yeehaw!" is a slang phrase used by cowboys, typically said out of excitement or something similar.
"Yeenhaw," however is a twist on the western phrase for furries; specifically hyena furries.

Hyena furries, also known as yeens, may exclaim this phrase out of excitement. Yeens may also exclaim this phrase while riding horses, (or other things) similar to how western cowboys say "yeehaw" when riding a horse.