改革
かいかく · kaikaku · JLPT N1 · noun
reform
🐍 改 = change + 革 = leather/hide; shedding the old skin = reform
革 originally meant animal hide, and a snake shedding its skin is a way to replace the old covering. 改 means change, so 改革 is changing the old system, with new covering in place of old.
改 — 己 (self) + 攴/攵 (action/strike)
改 is a compound of 己 'self' and 攵 (the action radical, originally a hand holding a stick). The image is of striking or applying force to oneself or one's situation, suggesting reform or correction. From this came the modern meaning 'to change, alter, correct'.