There is a debate about the longest word in the English language; in my opinion it's floccinaucinihilipilificatious compared to the debate on
antidisestablishmentarianism. Those with
hippopotomonstrosesquippedaliophobia tend to avoid the subject. The longest word in the common English dictionary is pneumohoultramicroscopicsilicovolcanoko niosis, although in medical diaries and such methionylglutaminylarginyltyrosylglutam ylserylleucylphenylalanylalanylglutamin ylleucyllysylglutamylarginyllysylglutam ylglycylalanylphenylalanylvalylprolylph enylalanylvalylthreonylleucylglycylaspa rtylprolylglycylisoleucylglutamylglutam inylserylleucyllysylisoleucylaspartylth reonylleucylisoleucylglutamylalanylglyc ylalanylaspartylalanylleucylglutamylleu cylglycylisoleucylprolylphenylalanylser ylaspartylprolylleucylalanylaspartylgly cylprolylthreonylisoleucylglutaminylasp fraginylalanylthreonylleucylarginylalan ylphenylalanylalanylalanylglycylvalylth reonylprolylalanylglutaminylcysteinylph enylalanylglutamylmethionylleucylalanyl leucylisoleucylarginylglutaminyllysylhi stidylprolylthreoylisoleucylprolylisole ucylglycylleucylleucylmethionyltyrosyla lanylasparaginylleucylvalylphenylalanyl asparaginyllysylglycylisoleucylaspartyl glutamylphenylalanyltyrosylalanylglutam inylcysteinylglutamyllysylvalylglycylva lylaspartylserylvalylleucylvalylalanyla spartylvalylprolylvalylglutaminylglutam ylserylalanylprolylphenylalanylarginylg lutaminylalanylalanylleucylarginylhisti dylasparaginylvalylalanylprolylisoleucy lphenylalanylisoleucylcysteinylprolylpr olylaspartylalanylaspartylaspartylaspar tylleucylleucylarginylglutaminylisoleuc ylalanylseryltyrosylglycylarginylglycyl tyrosylthreonyltyrosylleucylleucylseryl arginylalanylglycylvalylthreonylglycyla lanylglutamylasparaginylarginylalanylal anylleucylprolylleucylasparaginylhistid ylleucylvalylalanyllysylleucyllysylglut amyltyrosylasparaginylalanylalanylproly lprolylleucylglutaminylglycylphenylalan ylglycylisoleucylserylalanylprolylaspar tylglutaminylvalyllysylalanylalanylisol eucylaspartylalanylglycylalanylalanylgl ycylalanylisoleucylserylglycylserylalan ylisoleucylvalyllysylisoleucylisoleucyl glutamylglutaminylhistidylasparaginylis oleucylglutamylprolylglutamyllysylmethi onylleucylalanylalanylleucyllysylvalylp henylalanylvalylglutaminylprolylmethion ylysylalanylalanylthreonylarginylserine reigns supreme. But in the science of deoxyribose nucleic acid (DNA) all amino acids have their own little tag. {eg. glutaminyl=C5H9N2O2 valyl=(CH3)2CHCH(NH2)CO} Therefore one strand of DNA could be lengthened out to an infinite amount of letters long.
The current longest accepted word in English dictionaries (above) is questioned also being as that it was coined by a man in 1935 simply for the purpose of creating a new longest word. Though pneumonoultramicroscopicsilicovolcanoco niosis does have a definition as a disease caused by inhalation of sulfuric dust in volcanic smoke, very prominent among mine workers and volcanic scientists.
As it is an open debate feel free to choose what you believe.
WARNING: Reading above "longest word" out loud may result in electroencephalographical complications.
