Not to put to fine a point on it, or debate, but according to Webster's II, it is the property or quality distinguishing living organisms and inanimate matter, manifested in functions such as growth, metabolism, response to stimuli, and reproduction, the physical and mental, and spiritual experiences that constitute a person's existence, the interval of time between birth and death, a manner of living, a source of vitality: animating force, something that actually exists regarded as a subject for an artist. It means a lot, the most important being keeping alive, I think.