pneumonoultramicroscopicsilicovolcanoconiosis
/ˌnjuːmə(ʊ)nəʊˌʌltrəˌmʌɪkrə(ʊ)ˈskɒpɪkˌsɪlɪkəʊvɒlˌkeɪnəʊˌkəʊnɪˈəʊsɪs
/noun [mass noun]
An invented long word said to mean a lung disease caused by inhaling very fine ash and sand dust.Pneumonoultramicroscopicsilicavolcanoconiosis is a form of the illness pneumoconiosis, caused by the inhalation of a fine silica dust found in most volcanoes....
- Thus, pneumonoultramicroscopicsilicovolcanoconiosis is a disease of the lungs resulting from the inhalation of very fine silicate or quartz dust
Origin
1930s: a word invented (probably by Everett M. Smith, president of the National Puzzlers' League) in imitation of very long medical terms.