English · Word Candidate

atom

/ˈætəm/

Proposed by a contributor, not yet supported by evidence.

Also seen as: atoms

Sense 1

Meaning · English

The smallest possible amount of matter which still retains its identity as a chemical element, now known to consist of a nucleus surrounded by electrons.

Noun

Examples

Oxygen levels on Earth skyrocketed 2.4 billion years ago, when cyanobacteria evolved photosynthesis: the ability to convert water and carbon dioxide into carbohydrates and waste oxygen using solar energy. The evolutionary precursor of photosynthesis is still under debate, and a new study sheds light

Usage example from English Wiktionary (CC BY-SA 4.0, retrieved 2026-08-01)

Sources & notes

Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-08-01 via kaikki.org).

Sense 2

Meaning · English

A hypothetical particle posited by Greek philosophers as an ultimate and indivisible component of matter.

Noun

Sources & notes

Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-08-01 via kaikki.org).

Common questions

What does “atom” mean?

The smallest possible amount of matter which still retains its identity as a chemical element, now known to consist of a nucleus surrounded by electrons.

Is “atom” formal or informal?

No register label has been reviewed yet — treat it as neutral and check the usage notes above.