The prominent bone on the side of the ankle, technically called the talus or fibula, that forms the bony protrusion you can feel at the ankle joint.
Compound word from English "ankle" (from Old Norse "öngull," meaning the joint where the foot meets the leg) and "bone." The compound emerged in medical and anatomical contexts.
Your anklebones are more mobile than you realize—they can move in three dimensions, which is why balancing on one foot is actually an incredibly complex feat that your brain has to compute constantly.
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