atomic

American  

[uh-tom-ik] / əˈtɒm ɪk /

Also atomical

adjective

1. of, pertaining to, resulting from, or using atoms, atomic energy, or atomic bombs.

   an atomic explosion.

2. propelled or driven by atomic energy.

   an atomic submarine.

3. Chemistry. existing as free, uncombined atoms.

4. extremely minute.

---

atomic British  

/ əˈtɒmɪk /

adjective

1. of, using, or characterized by atomic bombs or atomic energy

   atomic warfare

2. of, related to, or comprising atoms

   atomic hydrogen

3. extremely small; minute

4. logic (of a sentence, formula, etc) having no internal structure at the appropriate level of analysis. In predicate calculus, Fa is an atomic sentence and Fx an atomic predicate

---

atomic Scientific  

/ ə-tŏm′ĭk /

1. Relating to an atom or to atoms.

2. Employing nuclear energy.

---

Other Word Forms

• atomically
  adverb
• nonatomic
  adjective
• nonatomical
  adjective
• nonatomically
  adverb

Etymology

Origin of atomic

First recorded in 1670–80; atom + -ic

Explanation

Something that has to do with atoms is atomic. Atomic structure, for example, means the way an atom is organized and what it's made of. You'll often find the word atomic specifically describing power or weapons — in this case, atomic means the process of either splitting an atom, known as fission, or joining two atoms, fusion, to create energy. Also, every chemical element has its own atomic number, which is the number of protons in the nucleus of one of the element's atoms. Atomic comes from the Latin atomus, "indivisible particle," from the Greek atomos, "uncut" or "indivisible."

Example Sentences

“All of them point to a very serious increase in the capabilities,” Grossi, head of the U.N.’s International Atomic Energy Agency, told reporters during a visit to Seoul.

From The Wall Street Journal • Apr. 17, 2026

Modeling it on the Bulletin of the Atomic Scientists nuclear-destruction warning Doomsday Clock, he called it the Zero-Day Clock.

From The Wall Street Journal • Apr. 14, 2026

Strikes near the operating plant could cause "harmful consequences for people and the environment in Iran and beyond," said Rafael Grossi, director of the International Atomic Energy Agency.

From Barron's • Apr. 6, 2026

The International Atomic Energy Agency - the UN's nuclear watchdog - said it had been informed of the strike and had expressed "deep concern".

From BBC • Apr. 4, 2026

Only two months later, Congress’s Joint Atomic Energy Committee convened yet another in its seemingly endless string of hearings on the topic.

From "Big Science" by Michael Hiltzik

Related Words

• microscopic