脑 rarely appears alone in modern Chinese — it's mostly used as a component in compounds like 电脑 (computer, literally "electric brain"), 脑子 (brain/mind), and 头脑 (head/mind). You'll encounter the compounds far more often than 脑 by itself.
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The character contains the radical 月 (flesh/body radical, originally 肉) on the left, indicating it refers to a body part. Many body-part characters share this radical: 脸 (face), 胳 (arm), 腿 (leg).
