adverb. When "tardly" just doesn't cover the amplitude of the tarditude.
Real citation: "Earth to Funked, I wasn't talking about the WHOLE tardnet. Just a very small corner that attracts bombardments from some fantardistically tardtacular tards - MrMultiplePersonalityDisorder, Voss, etc."
(AKSWulfe, Aug. 6, 2004, http://18.104.22.168/search?q=cache:9xU3v8coLSYJ:forums.checksix.net/archive/index.php%3Ft-2221.html+fantardistically&hl=en&gl=us&ct=clnk&cd=1)
Made-up citation: "F-words to avoid when writing personal ads: 'fucknut,' 'fantardistically,' 'flaccid,' 'flatulent,' 'ferret-licking.'"