Origin: Originally depicted a thicket of thorny chū bushes (Vitex negundo), which were used as firewood or flexible whipping canes in ancient punishments, hence also conveying pain and suffering.

Semantic Evolution: From the thorny bush and the pain it inflicts, it came to mean suffering and punishment. Because the Chu state grew out of a distinct forested region, it also became the name of the state. Later, its association with clear visibility or distinctness derived from clearing out bushes.

• The State of Chu (楚国) was a massive and culturally distinct southern powerhouse during the Zhou Dynasty.
• The Chū bush branches were historically harvested to make chastisement rods.