迁徙 refers to the large-scale, often seasonal movement of people or animals from one region to another, typically for survival-related reasons such as finding food, breeding grounds, or milder climate. The character 迁 means 'to move (residence or location)' and carries a sense of deliberate, organized relocation; 徙 means 'to move (household or group)' and emphasizes collective movement. Together, they form a formal, literary term that conveys purposeful, often cyclical displacement—especially common in ecological, geographical, or historical contexts.

This word is rarely used for casual daily movement (e.g., commuting or changing apartments); instead, it evokes natural phenomena like bird migrations or human population shifts due to war, famine, or policy. It appears frequently in scientific writing, news reports on climate impacts, and documentaries about wildlife behavior. While grammatically a noun, 迁徙 can also function as a verbal noun (e.g., in phrases like '迁徙路线' — migration route) and is almost always modified by adjectives like '季节性' (seasonal) or '大规模' (large-scale).