腰痛 (yāo tòng) literally means 'waist pain' but specifically refers to lower back pain — discomfort or soreness in the lumbar region, between the bottom of the rib cage and the top of the buttocks. The character 腰 (yāo) means 'waist' or 'lower back', while 痛 (tòng) means 'pain' or 'ache'. Together, they form a compound noun used exclusively for medical or everyday descriptions of back discomfort, not general body aches.

This term is common in clinical settings, health discussions, and casual complaints — for example, when describing symptoms after lifting heavy objects, sitting too long, or due to age-related strain. Unlike broader terms like 疼痛 (téngtòng, 'pain' generally), 腰痛 is precise and anatomically specific. It does not imply severity; it can describe mild stiffness or acute, debilitating pain. In Chinese, it functions as a standalone noun and often appears with verbs like 有 (yǒu, 'to have'), 感觉 (gǎnjué, 'to feel'), or suffer from (患…).