energy >> /ˈɛnərdʒi/
Definition: [noun] The strength and vitality required for sustained physical or mental activity.
Example: changes in the levels of vitamins can affect energy and well-being
Definition: [noun] Power derived from the utilization of physical or chemical resources, especially to provide light and heat or to work machines.
Example: nuclear energy
Definition: [noun] The property of matter and radiation which is manifest as a capacity to perform work (such as causing motion or the interaction of molecules)
Example: a collision in which no energy is transferred