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

During heat treatment, nanoscale regions with slightly different atomic spacing begin to precipitate within the alloy. — Aman Tripathi, Interesting Engineering, 1 Oct. 2026

In Godzilla Minus Zero, a flashback to the bloody aftermath of Godzilla’s attack on Tokyo in 1947 in the first film is followed by one to Hiroshima in the wake of the 1945 atomic bombing. — Alison Willmore, Vulture, 30 Sep. 2026

Even the constituents of atoms—the protons and neutrons that make up atomic nuclei—couldn’t immediately coalesce. — Clara Moskowitz, Scientific American, 28 Sep. 2026

Lutetium is a heavyweight as far as other elements in atomic optical clocks go. — New Atlas, 24 Sep. 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