pneumonoultramicroscopicsilicovolcanoconiosisPronunciation: /ˌnjuːmənəʊˌʌltrəˌmʌɪkrə(ʊ)ˈskɒpɪkˌsɪlɪkəʊvɒlˌkeɪnəʊˌkəʊnɪˈəʊsɪʃ, njʊˌməʊnəʊ-/Definition of pneumonoultramicroscopicsilicovolcanoconiosis noun [mass noun] an artificial long word said to mean a lung disease caused by inhaling very fine ash and sand dust.
