calorifier (kÉËlÉrÉªËfaÉªÉ). 1  a water tank fitted with a coil, or coils, that can be heated in order to heat the water â â  The pressurised water supply is cold only: a calorifier is available at extra cost. Usage examples. 2  Trends. 3  a water tank fitted with a coil, or coils, that can be heated in order to heat the water â â  The pressurised water supply is cold only: a calorifier is available at extra cost.
In ecology, a population consists of all the organisms of a particular species living in a given area. For instance, we could say that a population of humans lives in New York City, and that another population of humans lives in Gross.
Definition of Population Density. In biology, populations are groups of individuals belonging to the same species that live in the same region at the same time. Population density is a measure of the number of organisms that make up a population in a defined area. Population density applies to all organisms on Earth, including the plants that make up vast crops, trees of the jungle, animals on the farm, fish in the ocean, and humans on the planet.