The longest word English word in the dictionary is: Pneumonoultramicroscopicsilicovolcanoconiosis. Although pneumonoultramicroscopicsilicovolcanoconiosis is in the dictionary, it's not really a real word. It's a made-up name for lung disease but it was created to mock long medical terms. What's the longest word not in the dictionary? The longest word not in the dictionary is the […] The post What is the longest word in the world? appeared first on Science Experiments for Kids.
