pneumonoultramicroscopicsilicovolcanoconiosis

an invented long word said to mean a lung disease caused by inhaling very fine ash and sand dust.

Pneumonoultramicroscopicsilicovolcanoconiosis is a term for a lung disease caused by inhaling silica dust, as in I had trouble breathing and my doctor diagnosed me with pneumonoultramicroscopicsilicovolcanoconiosis.