改革
gǎigé · HSK 5
reform
改 (change) + 革 (leather/hide) = reform; reshape the hide
革 originally meant animal hide stretched and reworked, extended to 'transform'. 改革 pairs 改 (alter) with 革 (renew) — literally 'alter and renew', i.e. reform.
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'.