energy level

American  

[en-er-jee lev-uhl] / ˈɛn ər dʒi ˌlɛv əl /

noun

1. a comparative level of capacity for vigorous activity.

   The child has a high energy level.

2. Also called energy state.  Physics. one of a quantized series of states in which matter may exist, each having constant energy and separated from others in the series by finite quantities of energy.

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energy level British  

noun

1. a constant value of energy in the distribution of energies among a number of atomic particles

2. the energy of a quantum state of a system. The terms energy level and energy state are often used loosely to mean quantum state . This is avoided in precise communication

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Etymology

Origin of energy level

First recorded in 1905–10

Example Sentences

The Fermi level represents the highest energy level electrons can occupy in a solid at absolute zero.

From Science Daily • Dec. 21, 2025

“And his energy level was so high. It felt like he must stay up 24 hours a day. So I hired him.”

From Los Angeles Times • Mar. 9, 2025

“It will definitely ramp up the energy level for Trump supporters,” he said.

From Slate • Jul. 16, 2024

First, WS2 absorbs light by sending an electron to a higher energy level.

From Science Daily • May 30, 2024

Martin apparently did not appreciate Cade Hernandez’s energy level.

From "100 Sideways Miles" by Andrew Smith