Methionylglutaminylarginyltyrosylglutamylserylleucylphenylalanylalanylglutaminylleucyllysylglutamylarginyllysylglutamylglysylalanylphenylalanylvalylprolylphenylalanylyalylthreonylleucylglcycylaspartylprolylglicylisoleucyglutamylglutaminlserylleucyllysylisoleucylaspartylthreonylleucylisoleucylglutamylalanylglyclyalanylaspartylalanylleucyglutamylleucylgluycylisoleucylproluylphenylalanyserylaspartyprolylleucelalanylaspartylglycylprolylthreonylisolleucyglutaminylasparaginylalanythreonylleucylarginylalanylphenylalanylalanylalanylglycylvalylthreonylprolylalanylglutaminylcysteinylphenylalanylglglutamylmethionylleucyalanylleucylisoleucylarginylglutaminyllysylhistidylprolyuthreonylisoleucylprolylisoleucylglycylleucylleucylmethionyltyrosylalanylasbaraginylleucylvalylphenylalanylsparaginyyllysylglycylisoleucylaspartylglutamylphenylalanylyltyrosylalanylglutaminylcysteinylglutamyllysylvalylglycylvalylspartylserylvalylleucylvallalanylaspartylvalylprolylvalvlglutaminylglutamylserylalanylprolylphenylalalrginylglutaminylalanylalanylleucylarginylhistidylasparaginylvalylanalprolylisoleucylphenylalanylisoleucylcysteinylprolyprolylaspartylalanylaspartylaspartyspartyleucylleucylarginylglutaminylisoleucylalanylseryltyroslglycylarginylglycyltyrosylthreonyltyrosylleucylleucylserylarginlalanylglycylvalylthreonylglycylalanylglutamylasparaginylarginylanylalanylleucylprolylleucylaspaaginylhistidylleucylvalylalanyllysylleucyllysylglutamyltyrosylasparagimylalanylalanyprolylprolylleucylglutaminylglycylphenlalanylglycylisoleyucylserylalanylprolylaspartylglutaminylvalyllysylalanylalanylisoleucylalspartylalanylglycylalanylalanylglycylalanylasoleucylserylglycylserylalanylisoleucylbalyllysylisoleucylisoleucylglutamylglutaminylhistidylasparaginylisoleucylglutamylpronylglutamyllysylmethionylluecylalanylalanyoeucyllysylvalylphenylalanylvalylglutamilylprolylmethionyllysylalanylalanylthreonylarginylserine
is the longest word in the English language. 1,909 letters long. It is a protein.
Some people don't consider that a real word. So the real real longest English word is supposedly
floccinaucinihilipilification,
meaning the act of estimating as worthless. 29 letters, used back in 1741.

(BTW, watch TV every day and one day you will see the GEICO commercial that uses this world in a spelling bee, most of u have already seen it, but still very funny commercial

)
pneumonoultramicroscopicsilicovolcanoconiosis (or pneumonoultramicroscopicsilicovolcanokoniosis),
is a lung disease. 45 letters.
Humuhumunukunukuapua'a,
AKA reef triggerfish, is Hawaii's official state fish. At 21 letters, it is supposedly longer than the fish itself.
Lipsmackinthirstquenchinacetastinmotivatingoodbuzzincooltalkinhighwalkinfastlivinevergivincoolfizzin Pepsi
was supposedly a type of Pepsi advertised in the 1970's. Pepsi company purposely used 100 letters for it.
Twoallbeefpattiesspecialsaucelettucecheesepicklesonionsonasesameseedbun
is a 71-letter word used to describe the Big Mac in a McDonald's commercial.
Nymphfly, rhythms, and sygyzy
are the longest words in the English language without a,e,i,o,u.
More info here:
http://en.wikipedia.org/wiki/Longest_word_in_the_English_language
Some more long words (don't know the credibility of these though, that's where I got the first word):
http://www.faqs.org/qa/qa-2245.html
OK, enough with English. I'll shut up now.
