矮树 (ǎi shù) literally means 'short tree' — 矮 (ǎi) means 'short' or 'dwarf', and 树 (shù) means 'tree'. Together, it refers to a tree that is naturally low-growing or has been cultivated to remain small in height, typically under 3–4 meters. Unlike shrubs (灌木), which lack a single main trunk, 矮树 retains a clear trunk and tree-like structure but stays compact. It’s commonly used in horticulture, landscaping, and bonsai contexts.

This term emphasizes stature rather than species: many types of trees — such as dwarf apple, dwarf cherry, or dwarf pine — can be called 矮树 when bred or pruned for reduced height. It’s neutral in register and appears in botanical descriptions, gardening guides, and ecological surveys. Note that 矮树 is not a taxonomic category but a descriptive, functional term based on growth habit.