ENGLISH
REFERENCE

radioactive

adj.
B2 Upper Intermediate US //ˌɹeɪdioʊˈæktɪv// UK //ɹˌeɪdɪəʊˈæktɪv// ra·dioac·tive Archaic

adj. sending out dangerous energy or particles because of changes inside an atom. You use this to describe things like nuclear fuel or certain medical equipment.

adj. emitting ionizing radiation or particles as a result of the spontaneous disintegration of atomic nuclei. Often modified by degree adverbs such as 'highly' or 'mildly'.


SIMPLE

The workers wear special suits to handle radioactive waste.

CONTEXTUAL

Scientists used a Geiger counter to detect if the soil samples were radioactive after the industrial accident.

COMPLEX

The disposal of radioactive isotopes requires specialized containment facilities designed to withstand geological shifts over thousands of years while preventing environmental contamination.

Antonyms
Origin

Coined by Pierre Curie and Marie Curie in 1898 as French radio-actif, equivalent to English radio- + active.

Usage

Typically used as an attributive adjective before a noun, though it can follow linking verbs.

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