‘鼻哼’ (bí hēng) is a technical term referring to a low, resonant, nasal grunt produced by exhaling air through the nose—often involuntarily or as a sign of mild discomfort, impatience, or nonverbal reaction. The character 鼻 means 'nose', indicating the anatomical source, while 哼 denotes a short, breathy vocalization typically made with closed or partially closed lips and vibrating nasal passages. Together, they form a compound noun that emphasizes both the physical origin and acoustic quality of the sound.

This term appears primarily in veterinary science, animal behavior studies, and phonetics—not in everyday conversation. It’s especially used to describe characteristic vocalizations in mammals like pigs, horses, or primates during social interaction or stress responses. Unlike the interjection ‘hēng’ alone—which can express disdain or skepticism—‘鼻哼’ is strictly descriptive and neutral, focusing on physiology rather than attitude.