What is the longest English wordwhat is the second longest word in the English language?

The first longest Word in English is Lopado­temacho­selacho­galeo­kranio­leipsano­drim­hypo­trimmato­silphio­parao­melito­katakechy­menolopado­temacho­selacho­galeo­kranio­leipsano­drim­hypo­trimmato­silphio­parao­melito­katakechy­meno which contains 183 letters. The second longest Word in English is PneumonoultramicroscopicsilicovolcanoconiOSis which contains 45 letters! It is pretty amazing! Look it up if you don't believe me! In fact if you look it up, you'll find a larger Word containing 189,819! Amazing!

floccinaucinihilipilification