I thought Supercalifragilisticexpialidocious is the longest word. Other say it is Methionylthreonylthreonylglutaminylala, but it’s not. So, what is the longest word?? According to the Newton dictionary the longest word in the world is Pneumonoultramicroscopicsilicovolcanoconiosis.
Pneumonoultramicroscopicsilicovolcanoconiosis pronounced as NOO-muh-noh-UL-truh-MY-kruh-SKOP-ik-SIL-i-koh-VOL-kay-no-koh-NEE-o-sis, is a noun. It is a lung disease caused by inhaling fine particles of silica.
The 45-letter word, Pneumonoultramicroscopicsilicovolcanoconiosis, was coined to serve as the longest English word and is the longest word ever to appear in an English language dictionary.