‘呼吸’ is a compound verb meaning 'to breathe'—the basic, involuntary physiological process of inhaling oxygen and exhaling carbon dioxide. The first character 呼 (hū) means 'to exhale' or 'to call out', while 吸 (xī) means 'to inhale' or 'to suck in'; together, they form a balanced, complementary pair representing the full cycle of breathing. Unlike many monosyllabic verbs in Chinese, 呼吸 is almost always used as a disyllabic unit and rarely split in everyday speech.

This word appears frequently in health, fitness, and medical contexts—for example, when discussing lung function, meditation techniques, or emergency care (e.g., 'check breathing'). It can also be used figuratively to describe something that 'breathes' metaphorically, like a city or ecosystem, though literal biological breathing remains its core meaning. As a verb, it typically follows subject–verb order and can take aspect particles like 了 or 着 (e.g., 呼吸着, 呼吸了).