‘雷声’ literally combines ‘雷’ (léi), meaning ‘thunder’ or ‘lightning’, and ‘声’ (shēng), meaning ‘sound’ or ‘voice’. Together, they form a compound noun meaning ‘thunderclap’—the loud, booming sound produced during a thunderstorm when lightning rapidly heats and expands the surrounding air. Unlike ‘闪电’ (lightning flash), which refers to the visual phenomenon, ‘雷声’ emphasizes the auditory experience.

This word is commonly used in weather descriptions, storytelling, idioms (e.g., ‘雷声大雨点小’ — ‘much thunder, little rain’, meaning big promises but little action), and children’s language. It appears frequently in both spoken and written Chinese, especially in contexts describing storms, natural phenomena, or metaphorical disruptions. While ‘雷’ alone can sometimes imply thunder colloquially, ‘雷声’ is the precise, unambiguous term for the sound itself and is never used for lightning visually.