What is the longest word in all the languages?

Answer 1

Acetylseryltyrosylserylisoleucylthreonylserylprolylserylglutaminyl-

phenylalanylvalylphenylalanylleucylserylserylvalyltryptophylalanyl-

aspartylprolylisoleucylglutamylleucylleucylasparaginylvalylcysteinyl-

threonylserylserylleucylglycylasparaginylglutaminylphenylalanyl-

glutaminylthreonylglutaminylglutaminylalanylarginylthreonylthreonyl-

glutaminylvalylglutaminylglutaminylphenylalanylserylglutaminylvalyl-

tryptophyllysylprolylphenylalanylprolylglutaminylserylthreonylvalyl-

arginylphenylalanylprolylglycylaspartylvalyltyrosyllysylvalyltyrosyl-

arginyltyrosylasparaginylalanylvalylleucylaspartylprolylleucylisoleucyl-

threonylalanylleucylleucylglycylthreonylphenylalanylaspartylthreonyl-

arginylasparaginylarginylisoleucylisoleucylglutamylvalylglutamyl-

asparaginylglutaminylglutaminylserylprolylthreonylthreonylalanylglutamyl-

threonylleucylaspartylalanylthreonylarginylarginylvalylaspartylaspartyl-

alanylthreonylvalylalanylisoleucylarginylserylalanylasparaginylisoleucyl-

asparaginylleucylvalylasparaginylglutamylleucylvalylarginylglycyl-

threonylglycylleucyltyrosylasparaginylglutaminylasparaginylthreonyl-

phenylalanylglutamylserylmethionylserylglycylleucylvalyltryptophyl-

threonylserylalanylprolylalanylserine is the longest word and comes from a book of chemical abstracts. It means Tobacco Mosaic Virus, Second Strain.

Answer 2

That is a bit subjective. There are many words that have been coined simply to try to have the record for being the longest word. Or some people count place names.

If one restricts themselves to non-made up words and no place names, than various scientific words for chemical compounds would be in the lead.

But if one restricts themselves to ordinary, non-specifically coined words, than all of those are around 20 to 40 letters.

In English, antidisestablishmentarianism is the longest by some standards, though incomprehensibilities is the longest in common use. The longest English word appearing in Dictionaries is:

Pneumonoultramicroscopicsilico - volcanoconiosis. (Hyphen was added to format)

The longest word in the world, without it being coined or contrived, and not for science, and not a place name, that I could find, was the 130 letter Swedish word:

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