What is the longest word in the dictionary?

Question

Once a panda came into town. He went to a restaurant and ate. The panda ordered bamboo. When he finished eating, he took out a gun and shot the waiter then left. Once the police found him, they asked the panda why he shot the waiter. The panda just replied " Look me up in the dictionary,". When the police did, they understood and let the panda go.

What was written in the dictionary?

Answer 1

Word Origin and History for pneumonoultramicroscopicsilicovolcanoconiosis Expand
n.
1962, "A facetious word alleged to mean 'a lung disease caused by the inhalation of very fine silica dust' but occurring chiefly as an instance of a very long word" [OED]. Said in an early reference to have been invented by seventh grade students in Norfolk, Virginia.

Answer 2

Smiles ((there is a mile between the two S's)