'峡谷' (xiá gǔ) is a compound noun meaning 'gorge' or 'canyon'—a deep, narrow valley with steep, rocky walls, typically formed by river erosion over long periods. The first character 峡 (xiá) means 'narrow pass' or 'defile', often referring to a constricted section between mountains or cliffs; the second character 谷 (gǔ) means 'valley' or 'ravine'. Together, they emphasize both the narrowness and the topographic depth characteristic of such landforms.

This word is commonly used in geography, travel writing, and nature documentaries. It appears in proper names like 雅鲁藏布大峡谷 (Yarlung Tsangpo Grand Canyon) and is preferred over more generic terms like 山谷 (shān gǔ, 'mountain valley') when describing dramatic, steep-walled formations. While it can appear in literary or descriptive contexts, it is neutral in register—not overly formal nor colloquial—and is widely understood across Mandarin-speaking regions.