A certain property of a body, expressed as a measurable quantity, such that when there is no communication of heat the quantity remains constant, but when heat enters or leaves the body the quantity increases or diminishes. If a small amount, h, of heat enters the body when its temperature is t in the thermodynamic scale the entropy of the body is increased by h / t. The entropy is regarded as measured from some standard temperature and pressure. Sometimes called the thermodynamic function.
I remember New York in the '80s as a place with vacant lots that would eventually give over to nature. Weeds would grow up, squirrels would move in. That entropy is gone now. It's too expensive to let a vacant lot go natural. Moby