What term encompasses all inhabitants of a particular town, area, or country?

The term that comprehensively refers to all inhabitants of a particular town, area, or country is "population." This is understood in demography as a collective of individuals residing within a defined geographical boundary, whether that be a small town, a larger city, or an entire country.

"Population" focuses on the total count of people and often includes various demographic factors such as age, gender, and ethnicity, but fundamentally, it refers to people as a whole within a specified location. This term is widely used in various fields, including geography, sociology, and environmental science, to analyze trends, resource distribution, and societal dynamics.

In contrast, "ecology" pertains to the study of interactions between organisms and their environment, not specifically focusing on human inhabitants. "Community" refers to a group of individuals who may interact socially or share common interests but does not necessarily encompass all individuals in a geographical area. "Ethnic group" defines a subset of the population characterized by shared cultural traits, language, or heritage, thereby being limited in scope when defining inhabitants overall.