IPA: /ˌsʌbˈpɒpjʊˌleɪʃən/
KK: /sʌbˌpɒp.jʊˈleɪ.ʃən/
A smaller group within a larger population that has specific characteristics or origins.
The researchers studied a subpopulation of the species to understand its unique traits.
Subpopulation → It is formed from "sub-" (meaning under or below) and "population" (from Latin "populatio", meaning people or population). The word refers to a group of people that exists under or within a larger population.
Think of a smaller group of people that exists 'under' ('sub-') a larger group ('population').