What Do You Call Someone Who Causes Commotion? English Language Needs a New Word

What you call someone who is causally and constantly causing chaos, controversy and commotion? I call that person a commoter! Many people believe it is not fair for me to make up new words and invent-a-words. Yet if you think about it there is no word for someone that causes commotion in the English language. We need to have such a word for these people who were constantly causing problems.

A commoter to a lesser degree is someone that promotes doom and gloom and is always telling you that the world will end and that everything that is going on, well they say it is so very critical and everything that someone says negatively turns into gossip. Bill O