ENGLISH
REFERENCE

radioactive

adj.
US //ˌɹeɪdioʊˈæktɪv// UK //ɹˌeɪdɪəʊˈæktɪv// ra·dioac·tive
  1. 1 emitting radiation (adj.)
    B2 Upper Intermediate Technical Science

    sending out energy in the form of rays or particles that can be harmful to living things.

    exhibiting radioactivity through the spontaneous emission of ionising radiation from unstable atomic nuclei.

    Example

    The workers wore special suits to protect themselves from the radioactive waste.

    Example

    The containment vessel was designed to withstand the intense heat and pressure generated by the radioactive decay of the spent fuel rods.

    Usage

    Usually precedes the noun it modifies.
  2. 2 dangerous or toxic (adj.)
    C1 Advanced Informal

    so controversial, dangerous, or unpleasant that people want to avoid it completely.

    highly controversial or socially toxic; used figuratively to describe individuals or topics that are perceived as damaging to associate with.

    Example

    After the scandal, the politician became radioactive and no one wanted to work with him.

    Example

    The proposed policy became politically radioactive after the leaked documents revealed the true cost to the taxpayers.

    Teacher's tip

    This is a common metaphorical use in business and politics to describe someone whose reputation is ruined.
Origin

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

Word family

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