Amusing English # 23 - Longest Word

Longest Word in the English Language without Repeating Letters 
The two 15 letter words uncopyrightable & dermatoglyphics are the words in the English language which do not have any letter repeated. 
Uncopyrightable : This word in simple terms means ineligible for copyright.

Dermatoglyphics : This word refers to the study of fingerprints and toe prints. 

Longest Word with All Vowels in Order
The 23 letter word ' Pancreaticoduodenostomy' happens to be the longest word in the English language which has all vowels in order of 'a, e, i, o, u'. This word Pancreaticoduodenostomy means a formation of an opening connecting the pancreas to the duodenum artificially by surgery.
 
Longest Word in which all letters Appear Twice
The 16 letter word ' Esophagographers' is the longest word in the English language that has all letters appearing twice! Quite an intriguing fact! An esophagographer is a person conducting the radiographic visualization of the food pipe of esophagus.
 
Longest Word with letters in Alphabetical Order
We have an amazing 8 letter word in the English language that consists of all its letters in alphabetical order. This word is ' aegilops', which in the medical dictionary stands for the fistula formed in the inner corner of the eye. In botanical terms it stands for great wild-oat grass.
 
Longest Word in the English Language
According to the Oxford Dictionary, the title of the longest word in the English language goes to the 45 letter word, 'Pneumonoultramicroscopicsilicovolcanoconiosis'.
 
Coined in 1935 by Everett M. Smith, the then president of the National Puzzlers' League, at its annual meeting, the word Pneumonoultramicroscopicsilicovolcanoconiosis is the name of a respiratory lung disease conduced by increased exposure to silica dust. Inhalation of microscopic silicone dust particles expelled from volcanic eruptions leads to this respiratory disease. Pronunciation of this word is difficult because of its length and for those with the fear of long words or Hippopotomonstrosesquippedaliophobia, this word seems to be all the more intimidating.
 
However, if we break it up it will become easier. Consider the pronunciation break up:
NYOO-muh-noh-ul-truh-my-kruh- skop-ik-SIL-i-koh-vol-kay-noh-koh-nee-OH-siss

Cheers!