Energy

noun
1. the capacity for performing work

2. power that makes machines work

3. the property of matter and radiation which is manifested as a capacity such as the interaction of molecules

1. The energy of the mind is the essence of life.
Aristotle

2. Law of Conservation of Energy: Energy cannot be created or destroyed, it can only be changed from one form to another.

3. The Sun’s energy is needed to sustain life. Every 1.5 millionths of a second, the Sun releases more energy than all humans consume in an entire year.