radioactive

/ˌɹeɪdiəʊˈaktɪv/

Proposed by a contributor, not yet supported by evidence.

Also seen as: radioactives

Sense 1

Meaning · English

Exhibiting radioactivity.

Adjective

Examples

As a matter of fact many of our best drinking waters have all sorts of unspecified qualities. Burton water, for example, is radioactive by Beetham's standards up to the ninth degree.

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

Any radioactive substance.

Noun

Examples

Any ship nearby will receive a lethal dose of gamma rays, neutrons, and other radioactives.

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).

Common questions

What does “radioactive” mean?

Exhibiting radioactivity.

Is “radioactive” formal or informal?

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