atomic

adjective

atom·​ic ə-ˈtä-mik How to pronounce atomic (audio)
1
a
: of, relating to, or concerned with atoms
atomic physics
b
: nuclear sense 2
atomic energy
2
a
: marked by acceptance of the theory of atomism
3
: minute
4
of a chemical element : existing in the state of separate atoms
atomically adverb

Examples of atomic in a Sentence

made atomic adjustments to the clock's mechanism to keep it from whirring as it ran
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
And that each electron is tiny in mass compared to each proton, neutrons, and atomic nucleus. Big Think, 16 Oct. 2025 As per the researchers, the results deepen the world’s knowledge at the atomic level. Georgina Jedikovska, Interesting Engineering, 16 Oct. 2025 Using these new attosecond X-ray laser pulses could allow scientists to study the fastest processes in materials at the atomic-length scale and to discern different elements. Thomas Linker, The Conversation, 15 Oct. 2025 Unlike nuclear fission which splits atoms of heavy elements, fusion combines two light atomic nuclei, releasing a large amount of energy with much less radioactive waste. Jeff Young, MSNBC Newsweek, 14 Oct. 2025 See All Example Sentences for atomic

Word History

First Known Use

1678, in the meaning defined at sense 1a

Time Traveler
The first known use of atomic was in 1678

Cite this Entry

“Atomic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/atomic. Accessed 20 Oct. 2025.

Kids Definition

atomic

adjective
atom·​ic ə-ˈtäm-ik How to pronounce atomic (audio)
1
: of, relating to, or concerned with atoms, atomic bombs, or nuclear energy
atomic physics
the atomic age
atomic energy
2
: extremely small
3
: found in the state of separate atoms
atomic hydrogen

More from Merriam-Webster on atomic

Last Updated: - Updated example sentences
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