Question

which is the longest word in dictonary and its meaning

Answer 1

pneumonoultramicroscopicsilicovolcanoconiosis

a disease that causes inflammation in the lungs owing to the inhalation of very fine silica dust.

Answer 2

so here is your answer.....
the longest word is - Pneumonoultramicroscopicsilicovolcanokoniosis. and its meaning is -a word that refers to a lung disease contracted from the inhalation of very fine silica particles ,specifically from volcano ;medically ,it is the same as silicosis.
hope it will help you