What is another word for pupil?

This Word does not let itself well to antonyms. Definition 1 - Student - You could say that the opposite might be "teacher", but I think that would be a stretch Definition 2 - The black "dot" in the middle of your eye - I don't have anything here. I don't really think you have have opposites of objects or items. You can really only have opposites when you are talking about adjectives (hot/cold) or adverbs (quickly/slowly). What is the opposite of a tree/person/rock? An anti-tree/anti-person/anti-rock?
teacher