鏡

Phono-semantic compound:

金 (쇠 금, “metal”) — semantic, indicating something made of metal (early mirrors were polished bronze).

竟 (마침내 경, “finally, completely”) — phonetic, providing the sound gyeong/ jìng/ kyō.

The composition conveys the idea of a shining polished metal surface that allows one to see an image.

Figuratively, 鏡 can also mean a model, example, reflection of virtue (e.g., “to take someone as a mirror”).

안경 (眼鏡) — glasses, spectacles

망원경 (望遠鏡) — telescope

현미경 (顯微鏡) — microscope

투영 (投影) — projection, casting an image

In classical Chinese, 鏡 referred specifically to bronze mirrors, highly polished to reflect.

In modern Chinese (Mandarin): jìng — “mirror, lens,” especially in compounds like 眼鏡 (glasses).