楚
ソ, ショ, いばら, しもと, すわえ

whip, cane

JLPT0 G13 S0 F5000

As per 疋# (point in opposite directions) + 林 forest (→ luxuriant growth) → plant/shrub with numerous thorns pointing in opposite directions → *thorn* plant (compare 朿) → *whip* (← implement with thorns or thorn-like protrusions). *Plain* and *clear* are borrowed meanings.

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