Discover your Patronus
Expecto Patronum is correct classical Latin for "I await a protector". A full-fledged (or corporeal) Patronus takes on a fixed animal form that is often significant to the witch or wizard casting the charm. Patronuses summoned by a particular person have been known to change, although this has only been observed in the books in cases of unrequited love, such as Tonks' and Snape's respective Patronuses. In these cases, the new Patronus takes on the form of an animal associated with the love interest.
Unlike many other 'find out what your patronus looks like' tests out on the web, mine gives some options. I chose to use the 'Big five' personality traits in psychology to help determine which animal would be conjured from your patronus charm. In the results I first give a brief description of what type your patronus would be. Then I list a few possible animals that match up with that description. You can then add your own thoughts to that list and hopefully better help you decide which animal would best fit.