virundum

Etymology
The term comes from a mishearing of the first line in the : “Ouviram do Ipiranga as margens plácidas” (misheard as “O virundum Ipiranga...”), but the origin of the mondegreen sense as in English is.

A folk etymology states it was in O Pasquim and made popular by  cartoons. On the internet, one of the oldest attestations comes from the 2003 blog Virunduns.

Noun

 * 1)  mondegreen