1. The sound one makes after being told an extremely bad, old and/or corny joke.
2. A way to describe an old, obvious and/or corny joke.
Derived from the trumpet sound from the golden age cartoons after a very obvious joke or gag was performed.
Roger made so many bad plays on words, in leiu of calling himself "funny" he called himself, "Punny."
The crowd responded with a "WHANT WAH!"
The joke was so bad it was referred to as a "whant wah" joke.