‘杂音’ (zá yīn) literally combines ‘杂’ (zá), meaning ‘mixed,’ ‘miscellaneous,’ or ‘disordered,’ and ‘音’ (yīn), meaning ‘sound’ or ‘tone.’ Together, they refer specifically to unwanted, interfering sounds—most commonly electrical noise in audio equipment (like static on a radio or buzzing in headphones) or abnormal acoustic signals in medical contexts (such as heart murmurs detected with a stethoscope). Unlike general words for ‘noise’ like 噪音 (zào yīn), 杂音 emphasizes irregularity, randomness, and functional disruption rather than just loudness or annoyance.

This term is frequently used in technical, medical, and audio engineering settings. In medicine, doctors listen for cardiac or pulmonary 杂音 to diagnose conditions; in electronics, engineers troubleshoot circuitry to eliminate 杂音 from signals. It’s a formal, precise term—not used colloquially for everyday background noise like traffic or chatter.