‘咳嗽’ is a verb meaning 'to cough'—the involuntary, forceful expulsion of air from the lungs, often to clear the throat or airways. Though written with two characters, 咳 and 嗽 are both individually related to coughing sounds or actions: 咳 refers more specifically to the sharp, dry sound of a cough, while 嗽 often implies a deeper, wetter, or more phlegm-related cough. Together, they form a common disyllabic verb used in everyday speech and medical contexts alike.

This word is neutral in register and appears frequently when discussing colds, allergies, smoking effects, or respiratory health. It can function as the main verb in a sentence (e.g., 他咳嗽了) or appear in compound structures like 咳嗽声 (coughing sound) or 慢性咳嗽 (chronic cough). Unlike some single-character verbs, 咳嗽 is rarely used alone as a noun without modification—it’s primarily verbal, though it may serve as a nominalized subject or object when context permits (e.g., 咳嗽很严重).