The term "refugee crisis" refers to a situation in which there is an influx of refugees into a particular country or region, often as a result of war, persecution, or natural disaster. This can put strain on resources and create challenges for the receiving communities, who must find ways to support and integrate the new arrivals while also addressing their own needs. The phrase is used to describe both short-term emergencies, as well as longer term trends of increased migration due to political instability or environmental factors.