The word "开始" is formed by combining two characters, each contributing a core meaning to create a new, composite concept. The first character, "开" (kāi), carries the fundamental idea of "to open", "to initiate", or "to start". It is paired with "始" (shǐ), which means "beginning", "commencement", or "origin". Together, they form a coordinated compound where both elements reinforce and specify the same central notion of an action's inception, effectively meaning "to begin" or "to start".