noun - (physics) a thermodynamic quantity equivalent to the capacity of a physical system to do work; the units of energy are joules or ergs
noun - an imaginative lively style (especially style of writing)
noun - a healthy capacity for vigorous activity
noun - the federal department responsible for maintaining a national energy policy of the United States; created in 1977
noun - forceful exertion
noun - enterprising or ambitious drive
noun - any source of usable power