ground state

American  

noun

Physics.

1. the state of least energy of a particle, as an atom, or of a system of particles.

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ground state British  

noun

1. the lowest energy state of an atom, molecule, particle, etc Compare excited

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ground state Scientific  

1. The state of a physical system having the lowest possible potential energy. For example, an electron in the lowest energy orbital in a hydrogen atom is in a ground state. The ground state of a physical system tends to be stable unless energy is applied to it from the outside; states that are not the ground state have a tendency to revert to the ground state, giving off energy in the process.

2. Compare excited state

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Etymology

Origin of ground state

First recorded in 1925–30

Compare meaning

How does ground-state compare to similar and commonly confused words? Explore the most common comparisons:

• ground state vs. excited state
• excited vs. ground state

Example Sentences

"Superfluidity is generally regarded as the low-temperature ground state," said Li.

From Science Daily • Feb. 5, 2026

"Today, precise state-led strikes, backed by central paramilitary forces, have changed the game. While paramilitary held the ground, state forces gathered intelligence and launched targeted operations. It was clear role delineation and coordination," he said.

From BBC • May 27, 2025

"We are very enthusiastic about the new insights that pushing these fibers into the quantum ground state will bring," emphasizes the research group leader.

From Science Daily • Jan. 18, 2024

The two states of the qubit correspond to two energy states of this artificial atom: its lowest energy state, which is known as the ground state, and the next one up.

From Scientific American • Sep. 28, 2023

Cements, in the form of pats, briquettes, cubes, cylinders, and in a loose ground state, and also mortars and concretes in cube, cylinder, and slab form, are subjected to sea water.

From Transactions of the American Society of Civil Engineers, vol. LXX, Dec. 1910 Federal Investigations of Mine Accidents, Structural Materials and Fuels. Paper No. 1171 by Wilson, Herbert M.