Modern simplified form rebuilt from complex traditional 肅, which originally depicted a hand holding a writing brush (聿) over a deep pool — a scribe in concentrated reverence. The simplification telescoped the lower portion into stylised crossing strokes. Indexed under Kangxi #129 聿 (yù) by tradition, though no visible 聿 survives.
Filed under radical 聿 (yù) by convention. 聿 is not a separate component in 肃, so no strokes are highlighted.
