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

The site will probe the internal structure of protons, neutrons and atomic nuclei with unprecedented precision. — Georgina Jedikovska, Interesting Engineering, 12 Aug. 2026

Citi's research supports that view, describing decentralized finance's reliance on an atomic clearing process, meaning delivery and payment happen simultaneously, as a change that cuts counterparty and settlement risk. — Malana Vantyler, jsonline.com, 11 Aug. 2026

Advertisement For decades, public memory has elevated Hiroshima into a universal symbol of the tragedy of war and horror of atomic weapons, while allowing Nagasaki to fade into the background. — James M. Scott, Time, 10 Aug. 2026

Mayor Shiro Suzuki said that while some countries argue the possession of nuclear weapons helps deter potential attackers, the atomic bombings of Hiroshima and Nagasaki had demonstrated that humans can cross the line. — ABC News, 9 Aug. 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