There are multiple answers to this question. For example, a magician studies performance magic- magic that is not real, but instead simply an illusion. Here are more names for real magic practitioners that you might find in a fantasy themed book:
- Mage (this isn't very commonly used, but its defenition is: a magician)
- Wizard (WAY more common, but mostly someone who uses spells rather than natural powers)
- Witch (by the loosest defenition, witches DO practice magic, but they are very stereotyped- the defenition of witch is: a person, now especially a woman, who professes or is supposed to practice magic, especially black magic or the dark arts)
- Sorcerer/Sorceress (a sorcerer, very literally, is a witch that practices more conjuring than simply potions and black magic)
I hope that this is helpful!