‘噪声’ (zàoshēng) literally combines ‘噪’ (zào), meaning ‘to make a harsh, grating sound’, and ‘声’ (shēng), meaning ‘sound’ or ‘voice’. Together, they form a technical term for unwanted, disruptive, or meaningless sound—especially in engineering, acoustics, and signal processing. Unlike the more general word ‘声音’ (shēngyīn), which simply means ‘sound’, ‘噪声’ carries a negative connotation: it implies interference, disturbance, or lack of useful information.

This term is widely used in contexts like environmental health (e.g., traffic or construction noise affecting well-being), electronics (electrical noise degrading signal quality), and medicine (e.g., background noise in hearing tests). It’s also common in daily life when discussing urban living, workplace safety, or audio equipment performance. While colloquially people may say ‘噪音’ (zàoyīn) with the same meaning—and the two are often interchangeable—‘噪声’ is preferred in formal, scientific, and regulatory documents in mainland China.