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

• tiny
• minuscule
• miniature
• microscopic
• microscopical

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

In 1917 Ioffe became the founding director of the Petrograd (later Leningrad) Physical Technical Institute, the center of atomic studies in the Soviet Union. —Literary Hub, 23 Oct. 2025

Researchers have shown how a quantum computer can be used to do nuclear magnetic resonance, a method of estimating the atomic structure of compounds. —Reed Albergotti, semafor.com, 22 Oct. 2025

This one strikes a mid-century chord with its wide face and retro time display, with an atomic dial and silent-sweep movement to maximize quietness. —Julia Harrison, Architectural Digest, 21 Oct. 2025

And that each electron is tiny in mass compared to each proton, neutrons, and atomic nucleus. —Big Think, 16 Oct. 2025

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