Population, n.
Etymology: [L. populatio: cf. F. population.]
1. The act or process of populating; multiplication of inhabitants.
2. The whole number of people, or inhabitants, in a country, or portion of a country; as, a population of ten millions.
Shades of meaning
Fernald has no entry of its own for population; he lists it under people.
Where he writes about it:
The population of a country is simply the aggregate of persons residing within its borders, without reference to race, organization, or allegiance; unnaturalized residents form part of the population, but not of the nation, possessing none of the rights and being subject to none of the duties of citizens. — from people