牛角 (niú jiǎo) literally means 'cow horn' — a compound noun formed by combining 牛 (niú, 'cow' or more broadly 'cattle') and 角 (jiǎo, 'horn'). Though it specifies the horn of a cow, in practice it’s often used generically for horns of cattle, water buffalo, or even figuratively to refer to horn-shaped objects. It appears in contexts ranging from biology and agriculture to traditional crafts (e.g., horn combs or carved ornaments) and folklore (e.g., mythological creatures with ox-like features).

The term is neutral in register and commonly understood across dialects. Unlike some animal-part terms that require classifiers in specific constructions, 牛角 itself functions as a standalone noun — for example, you’d say 一根牛角 (yī gēn niú jiǎo, 'one horn') using the classifier 根 (gēn) for long, slender objects. It’s not used for deer antlers (which are 鹿角 lù jiǎo) or rhino horns (犀牛角 xī niú jiǎo), which have distinct names.