1)The event in which pumice (an extremely light non dense pyroclastic vasicular rock) is blown by a breeze and acts in the same fashion as a tumble weed.
2) The title of the holiday/celebration/festivities/fiesta held on May 10th, during which one celebrates whatever they damn well please, however they damn well please.
*in both cases they got that pyroclastic flow*
1) Dude check out that Tumble Pumice, is practically the tumble weeds of the geological realm
2) Man, I got so blasted at my Tumble Pumice yesterday, and basically puked out my entrails
3) Rob Schneider is ... a tumble pumice?