If you don't know, a hippopotomonstrosesquipedalian is a long word. For your pointless enjoyment, here's my collection of them.
Antidistablishmentarianism
- Pronounced an"tE-dis"u-stab"lish-mun-târ'E-u-niz"um
- Opposition to the withdrawal of state support or recognition from an established church, esp. the Anglican Church in 19th-century England
Honorificabilitudinitatibus
- From medieval Latin and means "with honourableness"
- Longest word which appears in Shakespeare's writings and comes from Love's Labour's Lost (Act 5, Scene 1, line 44)
Trinitrophenylmethylnitramine
- Pronounced trI-nI'trO-fen'l-meth'ul-nI"tru-mEn
- Tetryl
Floccinaucinihilipilification
- Pronounced flok"su-nô"su-nI"hil-u-pil"u-fi-kA'shun
- The estimation of something as valueless
Supercalifragilisticexpialidocious
pneumonoultramicroscopicsilicovolcanoconiosis
- Pronounced "new-mono-ultra-micro-scopic-silico-volcanic-coniosis"
- Lung disease caused by the inhalation of very fine silica dust
Other various long words:
-immunoelectrophoretically
-psychophysicotherapeutics
-thyroparathyroidectomized
-pneumoencephalographically
-radioimmunoelectrophoresis
-psychoneuroendocrinological
-antidisestablishmentarianism
-hepaticocholangiogastrostomy
-spectrophotofluorometrically
-floccinaucinihilipilification
-pseudopseudohypoparathyroidism
-metaphysico-theologo-cosmolonigology
-aminoheptafluorocyclotetraphosphonitrile
The longest official word ever (1,913 letters) is the term for the formula C1289-H2051-N343-O375-S8
It is the chemical name of the protein part of the tobacco mosaic virus:
Methionylglutaminylarginyltyrosylglutamylserylleuc ylphenylalanylalanylglutaminylleucyllysylglutamyla rginyllysylglutamylglycylalanylphenylalanylvalylpr olylphenylalanylyalylthreonylleucylglycylaspartylp rolylglycylisoleucylglutamylglutaminylserylleucyll ysylisoleucylaspartylthreonylleucylisoleucylglutam ylalanylglycylalanylaspartylalanylleucylglutamylle ucylglycylisoleucylprolylphenylalanylserylaspartyl prolylleucylalanylaspartylglycylprolylthreonylisol eucylglutaminylasparaginylalanylthreonylleucylargi nylalanylphenylalanylalanylalanylglycylvalylthreon ylprolylalanylglutaminylcysteinylphenylalanylgluta mylmethionylleucyalanylleucylisoleucylarginylgluta minyllysylhistidylprolylthreonylisoleucylprolyliso leucylglycylleucylleucylmethionyltyrosylalanylaspa raginylleucylvalylphenylalanylasparaginyllysylglyc ylisoleucylaspartylglutamylphenylalanyltyrosylalan ylglutaminylcysteinylglutamyllysylvalylglycylvalyl aspartylserylvalylleucylvalylalanylaspartylvalylpr olylvalylglutaminylglutamylserylalanylprolylphenyl alanylarginylglutaminylalanylalanylleucylarginylhi stidylasparaginylvalylalanylprolylisoleucylphenyla lanylisoleucylcysteinylprolylprolylaspartylalanyla spartylaspartylaspartylleucylleucylarginylglutamin ylisoleucylalanylseryltyrosylglycylarginylglycylty rosylthreonyltyrosylleucylleucylserylarginylalanyl glycylvalylthreonylglycylalanylglutamylasparaginyl arginylalanylalanylleucylprolylleucylasparaginylhi stidylleucylvalylalanyllysylleucyllysylglutamyltyr osylasparaginylalanylalanylprolylprolylleucylgluta minylglycylphenylalanylglycylisoleucylserylalanylp rolylaspartylglutaminylvalyllysylalanylalanylisole ucylaspartylalanylglycylalanylalanylglycylalanylis oleucylserylglycylserylalanylisoleucylvalyllysylis oleucylisoleucylglutamylglutaminylhistidylasparagi nylisoleucylglutamylprolylglutamyllysylmethionylle ucylalanylalanylleucyllysylvalylphenylalanylvalylg lutaminylprolylmethionyllysylalanylalanylthreonyla rginylserin