atomic

adjective

atom·​ic ə-ˈtä-mik How to pronounce atomic (audio)
Synonyms of atomicnext
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
b
: atomistic sense 2
3
: minute
4
of a chemical element : existing in the state of separate atoms
atomically
ə-ˈtä-mi-k(ə-)lē How to pronounce atomic (audio)
adverb

Synonyms of atomic

Relevance
See All Synonyms & Antonyms in Thesaurus

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.
Many of the heaviest elements arise only in environments where lots of free neutrons crash into atomic nuclei at great velocities. — Robin George Andrews, Scientific American, 20 Oct. 2026 Imagine a perfect replica of a sprawling metropolis, a Tokyo or a São Paulo, engraved at atomic dimensions on a tile the size of a fingernail. — Gideon Lewis-Kraus, New Yorker, 19 Oct. 2026 Tests like isotopic analyses — measuring subtle differences in the atomic makeup of elements — can help identify the samples' origins by comparing their chemical fingerprints with those of Martian rocks and asteroid material. — Josh Dinner, Space.com, 18 Oct. 2026 Unlike conventional crystals, whose atomic structures repeat in space, these experimental materials also display organized movement over time. — Neetika Walter, Interesting Engineering, 14 Oct. 2026 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

Phrases Containing atomic

Rhymes for atomic

See All Rhymes for atomic

Browse Nearby Words

atom beam
atomic
atomic absorption spectrometer
See all Nearby Words

Cite this Entry

“Atomic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/atomic. Accessed 27 Oct. 2026.

Copy Citation

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
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Last Updated: - Updated example sentences

More from Merriam-Webster

Word of the Day

Listen to the pronunciation of milieu

See Definitions and Examples »

Popular in Grammar & Usage

See More

How to Use 'Who' vs. 'Whom'

Merriam-Webster’s Great Big List of Words You Love to Hate

'Affect' vs. 'Effect'

'A' or 'an'? What about before 'h'? An Indefinite Article Guide

Why is '-ed' sometimes pronounced at the end of a word?
See More

Popular in Wordplay

See More

The Longest Long Words List

9 Words That Sound Like Insults But Aren't

12 Lovely and Unusual Words for the Natural World

Why do we 'bury the lede?'

'Za' and 9 Other Words to Help You Win at SCRABBLE
See More

Popular

See More

How to Use 'Who' vs. 'Whom'

The Longest Long Words List

9 Words That Sound Like Insults But Aren't
See More

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
The Missing Letter A daily crossword with a twist
different halloween monsters in silhouette
A Monstrous Vocab Quiz Words That Go Bump in the Night
See All