This is the 436th most frequent Korean word.
인구
Population.
In this sentence, '인구' is used to denote the total number of people on Earth.
세계 인구는 계속 증가하고 있습니다.
The world's population is continuously increasing.
Here, '인구' refers to the total number of people residing in a particular area, specifically Seoul.
서울의 인구는 천만 명이 넘습니다.
The population of Seoul exceeds ten million.
Here, '인구' is used in a context discussing the number of people per area, part of the term for population density, '인구 밀도'.