Neodymium (element)
釹 is a rare character used specifically for the chemical element neodymium. It has no other common standalone meanings.
釹 is a modern character created for the element neodymium, combining the metal radical 金 with the phonetic component 女 (ジョ).
The metal radical 金 hints at a metallic element, and the right side 女 (woman) can remind you of the 'neo' sound in neodymium, like a new woman of metals.
For ジョ, imagine a woman (女) named Jo who discovered this metal: Jo -> ジョ, and she holds a piece of neodymium.
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