all the people living in a particular country, area, or place

Ten percent of the population lived in poverty. 10%的人口生活在贫困之中。

In 1992 the population of Cairo was approximately 6,500,000. 1992年开罗的人口约为650万。

a growing/shrinking population 增长／逐渐减少的人口

Throughout the war, there were horrific casualties among the civilian populations of both countries. 整个战争期间，两国平民伤亡惨重。

The UN is investigating new methods of population control (= limiting the growth of the number of people). 联合国正在研究控制人口的新方法。

The country is facing a population explosion (= sudden growth in the number of people). 这个国家正面临着一场人口爆炸。

all the people or animals of a particular type or group who live in one country, area, or place

There's been a nine percent rise in the prison population (= the number of people in prison). 监狱收押人数上升了9%。

The dolphin population has been decimated by tuna fishing. 捕捞金枪鱼导致海豚的数量大大减少。