Pneumonoultramicroscopicsilico volcano 

Pneumonoultramicroscopic silico volcano coneosis (45 letters -- had to misspell it to fit in Urban Dictionary -- merge all of the words togeather); a lung disease caused by breathing in certain particles) is the longest word in any English-language dictionary. (It is also spelled -koniosis.)
On Feb. 23, 1935, the New York Herald-Tribune reported on page 3:

Pneumonoultramicroscopicsilico volcano-koniosis succeeded electrophotomicrographically as the longest word in the English language recognized by the National Puzzlers' League at the opening session of the organization's 103d semi-annual meeting held yesterday at the Hotel New Yorker.
The puzzlers explained that the forty-five-letter word is the name of a special form of silicosis caused by ultra-microscopic particles of siliceous volcanic dust.

His Pneumonoultramicroscopicsilico volcano koniosis made him cough-up black phlegm and blood.

Pneumonoultramicroscopicsilico volcano by Aaron M Smith October 17, 2006

Pneumonoultramicroscopicsilicovolcanoconiosophobia

The Phobia of being close to a volcano, silica dust(which you can't see), and getting pneumonoultramicroscopicsilicovolcanoconiosis.

Im going to a volcano.. Someone: NOT THIS CLOSE THOUGH! Me: uhhh... I think you have pneumonoultramicroscopicsilicovolcanoconiosophobia?

Pneumonoultramicroscopicsilicovolcanoconiosophobia by ƪĄİŁÞĞĐĶŪŒƏəŢĶÑØĽĢŘßĶŐŁŚ§ÇĶ£€ May 22, 2022

pneumonoultramicroscopicsilicovolcanoconiosis 

An inflammation of the lungs caused by microscopic grains of certain types of rock.

*NOTE* This word was actually coined in a deliberate attempt to be the longest word in the english language, although you would be hard-pressed to find it in the language dictionary as it is a medical/scientific term.

"Dude, now that I've learned how to spell antidisestablishmentarianism, what am I going to do to make people think I'm smart?"

"Quiet man, I'm trying to name this condition we discovered today. Its an inflammation of the lungs caused by microscopic grains of certain types of rock."

"Hey, I smell opportunity! How long could we make this word?"

"Pretty long...I suppose we could stretch it to pneumonoultramicroscopicsilicovolcanoconiosis"

pneumonoultramicroscopicsilicovolcanoconiosis by Fludence March 9, 2009

pneumonoultramicroscopicsilicovolcanoconiosis 

The wifi password

A: What's the wifi password?
B: It's on the back of the router.
The router: pneumonoultramicroscopicsilicovolcanoconiosis

pneumonoultramicroscopicsilicovolcanoconiosis by HeavenlyCheeseGod March 19, 2021

pneumonoultramicroscopicsilicovolcanoconiosis'd've'ly'yaint'nt'ed'ies's'y'es'nt'ed'ies's'y'es'nt't're'ing'able'ric'ive'al'nt'ne'm'll'ble'al 

the longest possible grammatically correct EVER.

man i really pneumonoultramicroscopicsilicovolcanoconiosis'd've'ly'yaint'nt'ed'ies's'y'es'nt'ed'ies's'y'es'nt't're'ing'able'ric'ive'al'nt'ne'm'll'ble'al ing hate this guy

pneumonoultramicroscopicsilicovolcanoconiosis'd've'ly'yaint'nt'ed'ies's'y'es'nt'ed'ies's'y'es'nt't're'ing'able'ric'ive'al'nt'ne'm'll'ble'al by easportstothegame June 16, 2020

pneumonoultramicroscopicsilicovolcanoconiosis 

1. A disease gotten from inhalation of diminative particles of silica or quartz.
Pneumono - Lung
Ultra Microscopic - Very small/fine
silico volcano - igneous, silica
coniosis - disease
; Black Lung

In the mid 1880's, miners would get pneumonoultramicroscopicsilicovolcanoconiosis.

pneumonoultramicroscopicsilicovolcanoconiosis by Kyle Zager January 6, 2005

pneumonoultramicroscopicsilicovolcanoconeousis 

A disease you get from inhaling ultra microscopic peices of volcano dust.

some random person: "What's pneumonoultramicroscopicsilicovolcanoconeousis?"
Me: "some really long disease name but its not the longest."
some random person: "So then what's the longest word?"
Me: "the chemical name for titin which is to long for me to type."
some random person: "Oookay, bye."

pneumonoultramicroscopicsilicovolcanoconeousis by hayNay November 21, 2018