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

Researchers have captured the most detailed look yet at how gold’s atomic structure changes under some of the highest pressures ever achieved in a laboratory. —Kaif Shaikh, Interesting Engineering, 21 Nov. 2025

Japan’s experience of the atomic bombings of Hiroshima and Nagasaki remains central to its collective memory. —Moritz S. Graefrath, Foreign Affairs, 19 Nov. 2025

At an atomic level, a particle can exist as both matter and energy simultaneously. —Jim Edwards, Fortune, 19 Nov. 2025

Instead the primordial cosmic soup would have been a blazing mess of the fundamental particles called quarks, as well as gluons, which carry the strong force that binds atomic nuclei together. —Clara Moskowitz, Scientific American, 15 Nov. 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