The word 刹车 is formed through semantic compounding, where two independent characters, each with their own meaning, combine to create a new, specific concept. The first character, 刹, originates as a Buddhist term meaning "to stop" or "cease". The second character, 车, simply means "vehicle" or "cart". By logically combining these ideas, the compound literally conveys "to stop a vehicle", which directly and intuitively refers to the action and mechanism of braking.