An official count or enumeration of members of a population (not necessarily human), usually residents or citizens in a particular region, often done at regular intervals.
Count, tally.
To collect a census.
To conduct a census on.
The particular demographic makeup of a population.
The study of the structure and population dynamics of other lifeforms, such as mammals, insects, plants, etc.
The study of the characteristics of human populations, especially with regards to their makeup and fluctuations and the social causes behind these.