曲線

きょくせん · kyokusen · JLPT N2 · noun

curve

🎢 曲 (kyoku) = bend + 線 (sen) = line, so 曲線 is a bent line

曲 comes from 曲がる (magaru), meaning to bend or turn. 線 means line. Put them together and you get a line that bends, the same word the Japanese use for a curve in a graph or road.

曲 — pictograph of a bent carpenter's tool or curved object
曲 is a pictograph showing a bent or curved shape, originally depicting a carpenter's measuring tool or a curved frame. From this concrete image of bending came the abstract senses of 'crooked,' 'wrong,' and 'tune/melody' (since songs follow winding contours). The reading qū carries the bending senses, while qǔ means 'song.'

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