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METHIONYLTHREONYLTHREONYGLUTAMINYLARGINYL … ISOLEUCINE 

Note the ellipses. All told, the full chemical name for the human protein titin is 189,819 letters, and takes about three-and-a-half hours to pronounce. The problem with including chemical names is that there’s essentially no limit to how long they can be. For example, naming a single strand of DNA, with its millions and millions of repeating base pairs, could eventually tab out at well over 1 billion letters.

Methionylthreonylthreonylglutaminylarginyltyrosylglutamylserylleucylphenylalanylalanylglutaminylleuc 

yllysylglutamylarginyllysylglutamylglycylalanylphenylalanylvalylprolylphenylalanylvalylthreonylleucylgl
ycylaspartylprolylglycylisoleucylglutamylglutaminylserylleucyllysylisoleucylaspartylthreonylleucylisoleu
cylglutamylalanylglycylalanylaspartylalanylleucylglutamylleucylglycylisoleucylprolylphenylalanylseryla
spartylprolylleucylalanylaspartylglycylprolylthreonylisoleucylglutaminylasparaginylalanylthreonylleucyl
arginylalanylphenylalanylalanylalanylglycylvalylthreonylprolylalanylglutaminylcysteinylphenylalanylglu
tamylmethionylleucylalanylleucylisoleucylarginylglutaminyllysylhistidylprolylthreonylisoleucylprolylisol
eucylglycylleucylleucylmethionyltyrosylalanylasparaginylleucylvalylphenylalanylasparaginyllysylglycyli
soleucylaspartylglutamylphenylalanyltyrosylalanylglutaminylcysteinylglutamyllysylvalylglycylvalylaspa
rtylserylvalylleucylvalylalanylaspartylvalylprolylvalylglutaminylglutamylserylalanylprolylphenylalanylarg
inylglutaminylalanylalanylleucylarginylhistidylasparaginylvalylalanylprolylisoleucylphenylalanylisoleuc

To make the longest word on urbandictionary.com i would need to fill out 127 word forms but im too retarded and lazy
Guy 1: Holy shit did you heat about Titin?!
Guy 2: You mean Methionylthreonylthreonylglutaminylarginyltyrosylglutamylserylleucylphenylalanylalanylglutaminylleuc?

Methionylthreonylthreonylglutaminylarginyl...isoleucine 

The longest known word in English, at 189,819 letters, is the chemical name of titin. Titin is the largest known protein. This word takes roughly 3 hours to pronounce.
I can't use the full chemical name of titin because it goes over the word limit. So heres a shortened form:
I just learned today that Methionylthreonylthreonylglutaminylarginyl...isoleucine is the chemical name of the largest known protein to mankind.

methionylthreonylthreonylglutaminylarginyltyrosylglutamylserylleucylphenylalanylalanylglutaminylleuc 

(Longest word in the english Language)
Used for...Titin? What the f*ck its a Titin...(Googles and sees the complicated shit. ) oh...well
Scientist: did you see my methionylthreonylthreonylglutaminylarginyltyrosylglutamylserylleucylphenylalanylalanylglutaminylleuc?
Scientist 2: No i did't see your methionylthreonylthreonylglutaminylarginyltyrosylglutamylserylleucylphenylalanylalanylglutaminylleuc

methionylthreonylthreonylglutaminylarginyl...isole 

A big ass word that mr. Beast read for over seventeen hours in a video.
Bab: Pneumonoultramicroscopicsilicovocanoconiosis is the biggest word
Beb: No, methionylthreonylthreonylglutaminylarginyl...isole is the biggest word!
Bab, Bib, Bob and Bub: IT'S ALMOST BEEN A FULL DAY, GO THE FUCK TO SLEEP

Methionylthreonylthreonylglutaminylarginyl...isoleucine 

A shortened version of the longest english word. The actual word has about 900,000 characters (189,819 to be specific). It is the chemical name for titin, which is the largest known protein. The word is obviously rarely used as it takes about 3 hours to pronounce, and it would be a lot quicker to just say "titin".
If you want some big protein, might want to look for something with a lot of Methionylthreonylthreonylglutaminylarginyl...isoleucine
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