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

• bitsy
• bitty
• infinitesimal
• itty-bitty
• itsy-bitsy
• little bitty
• microminiature
• microscopic
• microscopical
• miniature
• minuscule
• minute
• teensy
• teensy-weensy
• teeny
• teeny-weeny
• tiny
• wee
• weeny
• weensy

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

Early ideas had atomic and hydrogen fuels layered in alternating bands, similar to the insides of a baseball. —William J. Broad, New York Times, 19 May 2025

That means no ticky-tack stuff on Gilgeous-Alexander, and no WWE arm bars and atomic knee drops against Jokic. —Troy Renck, Denver Post, 17 May 2025

But Mars has atomic oxygen, and oxygen on Earth causes a green glow. —Lillian Ali, Smithsonian Magazine, 16 May 2025

This parameter is key for discovering whether such phenomena are made of just protons or heavier atomic nuclei — and, therefore, what produces them. —Keith Cooper, Space.com, 16 May 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