population growth

Population growth is the change in population over time, and can be quantified as the change in the number of individuals in a population per unit time. The term population growth can technically refer to any species, but almost always refers to humans, and it is often used informally for the more specific demographic term population growth rate (see below), and is often used to refer specifically to the growth of the population of the world.
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Noun
1. increase in the number of people who inhabit a territory or state
(hypernym) increase, increment, growth
(hyponym) irruption