How to pronounce pneumonoultramicroscopicsilicovolcanoconiosis

How to pronounce the longest word in the dictionary. What’s the longest word in the dictionary? pneumonoultramicroscopicsilicovolcanoconiosis
What does it mean?
pneumonoultramicroscopicsilicovolcanoconiosis
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.
Pronunciation
pneumonoultramicroscopicsilicovolcanoconiosis/ˌnjuːmə(ʊ)nəʊˌʌltrəˌmʌɪkrə(ʊ)ˈskɒpɪkˌsɪlɪkəʊvɒlˌkeɪnəʊˌkəʊnɪˈəʊsɪs/