遡 means “go upstream, trace back”

さかのぼる · sakanoboru

Also: retrace the past

Kun'yomi (Japanese reading)
さかのぼる
On'yomi (Chinese reading)
ソ, サク

JLPT N1 · Taught in secondary school · 13 strokes

The story

Walking (辶) back to 朔, the new moon that starts the month: going back to the beginning. 遡る is to go upstream, as salmon do in autumn, or back in time: a custom that 江戸時代に遡る dates back to Edo times.

Used in 遡る (sakanoboru, to go back/go upstream), 遡上 (sojou, swimming upstream), and 遡及 (sokyuu, retroactivity)

More from Routes & Returns

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Readings from KANJIDIC2, © EDRDG, CC BY-SA.