adj ~ a wonderful occurrence that is purely a lucky coincidence facilitated or created by a blunder; succeeding because of failure, rather than despite it
Sweetheart, you're the most blunderful thing to ever happen in your mother's and my lives.
Port-manteau of blunder and wonderful; a particularly egregious mistake, possibly of epic proportions. Usually the speaker is deeply affected by the fallout.
A: Oh, so I was just playing with your computer and, errr, I had to reinstall everything because I deleted your whole disk.
B: Blunderful!
A person who has reached the pinnacle of whatever it is that can be, this person is beyond time space and existence as we know it. To be called this is confirmation that you are one of the most based individuals to ever exist.
Short-hand for the word floccinaucinihilipilification, meaning the estimation of something as valueless (encountered mainly as an example of one of the longest words in the English language).