majo 魔女

In Japanese, majo 魔女 means "witch." In other words: a mahou-tsukai 魔法使い, "magic user," who is a "woman," onna 女.

The term majo implies an adult "woman." For a "girl-witch," the term majokko 魔女っ子 is used instead. A "witch's apprentice" would be a majo no minarai 魔女の見習い.

The term mahou shoujo 魔法少女, "magic girl," refers to a "magical girl," and the genre of anime that features magical girls. It's not the same thing as majo or majokko, although some mahou shoujo are also majokko.

The term majo can also be used to refer to a real, non-fictitious woman who can't use magic, but has some strange, mysterious power: she can achieve some amazing things, like she does magic.

It can also refer to a woman who's like a "demon," akuma 悪魔, tempting the heart of men: she's a witch!

The term bimajo 美魔女, literally a "beautiful," utsukushii 美しい, majo, refers to a woman who's older than 35 and tries to look younger than she is, doesn't let her age show: she doesn't look a day older than 25.

It can also refer to an older woman whose beauty remains despite her age, as if she was cast a magical spell that kept her beautiful through the decades: Magic Mirror, on the wall, who, now, is the fairest one of all?

This bimajo term follows the same pattern as bishoujo 美少女 and related terms.