Just looked it up. The Latin is actually bread in broth. Unless you are weird your cereal isn't in a broth. Sadly it appears the etymology goes further back to the German for consuming something liquid. I'm going to say though the nearest etymology you can find that actually refers to a food and not eating specifies broth. So thankfully cereal is not soup.It is technically a soup. The word soup comes from suppa, which is a Latin word that basically means bread soaked in liquid.