shake, vibrate, quake

震 is composed of 雨 (rain) and 辰 (time). 辰 depicts supports that prevent a cliff from collapsing and carries the meaning of shaking. Therefore, 震 conveys the idea of the shaking produced when thunder strikes on a rainy day. Its original meaning is a thunderclap or lightning strike, and later it came to broadly refer to any kind of shaking or vibration.