atomic

adjective

atom·​ic ə-ˈtä-mik 

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 

adverb

Synonyms of atomic

• tiny
• minuscule
• microscopic
• miniature

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

That includes using a technique called atomic interferometry or quantum sensors to make measurements across the solar system, such as lunar laser ranging, or on wider astronomical scales such as measuring the dynamics of planets. —Robert Lea, Space.com, 15 June 2026

Since the Islamic Revolution in 1979, Western nations have worried the country could use its nuclear program to produce atomic weapons. —Kevin Liptak, CNN Money, 14 June 2026

The idea is attractive because atomic nuclei are much smaller and more isolated from the outside world. —Rupendra Brahambhatt, Interesting Engineering, 13 June 2026

But the world, as any scientist probing into the atomic level can attest, contains more secrets than meets the eye. —Theater Critic, Los Angeles Times, 12 June 2026

Word History

First Known Use

1678, in the meaning defined at sense 1a

Phrases Containing atomic

• atomic bomb
• atomic clock
• atomic energy
• atomic force microscope
• atomic layer deposition
• atomic mass
• atomic mass unit
• atomic number
• atomic pile
• atomic reactor
• atomic theory
• atomic weight
• gram-atomic weight

Rhymes for atomic

• adamic
• anomic
• islamic
• meramec
• tokamak
• anatomic
• antidromic
• astronomic
• autonomic
• cryptogamic
• diatomic
• economic

Kids Definition

atomic

adjective

atom·​ic ə-ˈtäm-ik 

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