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population pop·u·la·tion (pŏp'yə-lā'shən)
The total number of people inhabiting a specific area.
The set of individuals, items, or data from which a statistical sample is taken.
All the organisms that constitute a specific group or occur in a specified habitat.
A group of individuals of the same species occupying a particular geographic area. Populations may be relatively small and closed, as on an island or in a valley, or they may be more diffuse and without a clear boundary between them and a neighboring population of the same species. For species that reproduce sexually, the members of a population interbreed either exclusively with members of their own population or, where populations intergrade, to a greater degree than with members of other populations. See also deme.
in human biology, the whole number of inhabitants occupying an area (such as a country or the world) and continually being modified by increases (births and immigrations) and losses (deaths and emigrations). As with any biological population, the size of a human population is limited by the supply of food, the effect of diseases, and other environmental factors. Human populations are further affected by social customs governing reproduction and by the technological developments, especially in medicine and public health, that have reduced mortality and extended the life span.