It can mean different things depending on the context in which it is used. Sometimes, essay" can be used as a synonym for "test" or "examination," in which case it would simply refer to a type of assessment that a student is taking. In other cases, "essay" may be used to refer to a piece of writing that is more informal and personal in nature, such as a blog post or personal essay. In either case, the word "essay" simply indicates that something is being written."