To be the Merriam-Webster word of the day. I thought it was a David Foster Wallace invention, but I was wrong:
"You have got strong symptoms of the fantods; your skin is so tight you can't shut your eyes without opening your mouth." Thus, American author Charles Frederick Briggs provides us with the oldest recorded use of "fantods" in 1839... The exact origin of "fantod" remains a mystery, but it may have arisen from English dialectal "fantigue"—a word (once used by Dickens) that refers to a state of great tension or excitement and may be a blend of "fantastic" and "fatigue."