The curved lines of hair above your eyes, or the ridges of bone and skin in that area.
From Old English 'bru' or 'brow,' related to Old Norse 'brú' meaning eyebrow. The word originally referred to the entire forehead area before narrowing to just the eyebrow region.
Your eyebrows are incredibly expressive—humans can recognize emotions from eyebrow position alone, which is why raised eyebrows mean surprise and lowered brows show anger, and these signals work across all cultures.
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