The "Longest Real Word" according to Guiness Book Of World Records is floccinaucinihilipilification. Got this in 1992 and subsequent editions. However words can be constructed with any length like for example "Bababadalgharaghtakamminarronnkonnbronntonnerronntuonnthunntrovarrhounawnskawntoohoohoordenenthurnuk" used by James Joyce in novel Finnegans Wake, or Pepsi used "Lip­smackin­thirst­quenchin­acetastin­motivatin­good­buzzin­cool­talkin­high­walkin­fast­livin­ever­givin­cool­fizzin" etc. However I like this one, "Taumatawhakatang­ihangakoauauot­amateaturipukaka­pikimaunga­horonuku­pokaiwhenuak­itanatahu" is a name of a hill in New Zealand, think its the longest name ever Smile does not quality as smiley surpasses it with one letter, hurraayyyyyyyyyyy. You know the shortest then? "D" its a river in England I believe. Just one letter, interesting Huh?