energy

noun

1.
(physics) a thermodynamic quantity equivalent to the capacity of a physical system to do work; the units of energy are joules or ergs
free energy
Derived from:
energize
2.
forceful exertion
vigor vigour zip
Derived from:
energetic energize
3.
enterprising or ambitious drive
get-up-and-go push
Derived from:
energetic energize
4.
an imaginative lively style (especially style of writing)
muscularity vigor vigour vim
Derived from:
energize
5.
a healthy capacity for vigorous activity
self-sparkle vim vitality
Derived from:
energetic energize
6.
any source of usable power