population (Noun) — The people who inhabit a territory or state. ex. "the population seemed to be well fed and clothed"
population (Noun) — A group of organisms of the same species inhabiting a given area. ex. "they hired hunters to keep down the deer population"
population (Noun) — (statistics) the entire aggregation of items from which samples can be drawn. ex. "it is an estimate of the mean of the population"
population (Noun) — The number of inhabitants (either the total number or the number of a particular race or class) in a given place (country or city etc.). ex. "people come and go, but the population of this town has remained approximately constant for the past decade" ex. "the African-American population of Salt Lake City has been increasing"
population (Noun) — The act of populating (causing to live in a place). ex. "he deplored the population of colonies with convicted criminals"