to hit something or someone with a half-erected (very important!) penis. the word was invented in Belgium - in the Flemish part of the country, where a variaton of Dutch is spoken. And yes, they're very proud of it.
A swaffler can always be spoted because it attracts pink elefants. to keep safe from them, always carry a green mouse with you.
There is a difference between a Brussel's waffle and a Brussel's swaffle