A lung disease caused by inhaling volcanic ash and/or dust. Can also be caused by inhaling very fine silica dust particles. Also, it is the longest English word to ever appear in a dictionary. It was first coined in 1931. The longest English word ever is the chemical name of titin ,the largest protein in the human body.
You won't have to use this word much, but if you have ever been near a volcano, and you start coughing like crazy, then you probably have pneumonoultramicroscopicsilicovolcanoconiosis.
by mkakapo January 29, 2014