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

Lutetium is a heavyweight as far as other elements in atomic optical clocks go. — New Atlas, 24 Sep. 2026

Extreme nuclear matter RHIC operated at BNL from 2000 to 2026 and was designed to investigate exotic forms of nuclear matter by colliding heavy atomic nuclei, like gold, at nearly the speed of light. — Georgina Jedikovska, Interesting Engineering, 23 Sep. 2026

Even a tiny amount of environmental noise, like the atomic jiggle of heat, can trigger decoherence, a collapse into classical behavior. — Elise Cutts, Quanta Magazine, 23 Sep. 2026

On rare occasions, however, one such particle could collide with an atomic nucleus and produce a tiny recoil — precisely the kind of event the LZ experiment is designed to detect. — Jacopo Prisco, CNN Money, 14 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