You really want to see what the word is, don't you? Well, for the sake of not taking up pages and pages filled with text , we can't exactly SHOW you the word in it's entirety. Although, the first few syllables of the word look like this "Methionylthreonylthreonylglutaminylarginyl"...and that's only the first 42 letters. Good luck spelling out this tongue twister at the next spelling bee.
This word actually has a much simpler form for scientists to refer to. Scientists refer to the word simply as 'titin' and the really long, 189,819 letter word is the chemical name of titin, the largest known protein.
However, there is much debate as to whether or not this anomaly is even a word, because it isn't in any dictionaries. If that's the case, the NEXT largest word is 1,909 letters long, which is impressive, but not nearly as impressive as 'titin'.
For a little bit of perspective, Antidisestablishmentarianism is only 28 letters long. Want to learn some more really long words? Click the source!