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nuclear

adj.
US //ˈnukɫiɝ// UK //njˈuːkliə// nu·cle·ar
  1. 1 atomic energy (adj.)
    B1 Intermediate Science

    relating to the energy produced when the center of an atom is split or joined.

    relating to or involving the energy released by nuclear fission or fusion.

    Example

    Many countries are building new nuclear power plants to create electricity without burning coal.

    Example

    The debate over nuclear energy often centers on the long-term management of radioactive waste versus the benefit of low-carbon power generation.
  2. 2 weapons (adj.)
    B1 Intermediate

    describing powerful weapons that use atomic energy to cause a massive explosion.

    denoting weapons that derive their destructive force from nuclear reactions.

    Example

    The two nations signed a treaty to reduce the number of nuclear missiles they owned.

    Example

    The proliferation of nuclear weaponry remains a primary concern for international security and diplomatic relations in the twenty-first century.
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  1. 3 family (adj.)
    B2 Upper Intermediate

    describing a small family group consisting only of parents and their children.

    relating to or constituting a family unit consisting of two parents and their offspring.

    Example

    In many modern cities, the nuclear family is more common than living with grandparents and cousins.

    Example

    Sociologists have noted that while the nuclear family was the twentieth-century ideal, diverse household structures are becoming increasingly prevalent.
  2. 4 biology (adj.)
    C1 Advanced Technical Biology

    relating to the nucleus, which is the control center of a living cell.

    pertaining to the nucleus of a biological cell.

    Example

    The scientist looked at the nuclear membrane under a powerful microscope.

    Example

    The study focused on how specific proteins are transported across the nuclear envelope to regulate gene expression.
  3. 5 extreme action (adj.)
    C1 Advanced Informal

    describing a very strong or extreme way of dealing with a problem.

    referring to an extreme or drastic course of action, often with irreversible consequences.

    Example

    The manager decided to go nuclear and fire the entire team after the project failed.

    Example

    The board threatened to go nuclear by cancelling the merger entirely if the new terms were not met by midnight.
Origin

From Latin nū̆cleus, a contraction of the adjective nuculeus, masculine of feminine nuculea (“pertaining to a small nut”) from nucula + adjectival suffix -eus, -ea, -eum. The Latin nucula + -āris adds up to nuculāris, a term that in English becomes nucular; the Latin nuculea + -āris, becomes Latin nuculeāris (“relative to what pertains to small nut”), later contracted into nuclear. By surface analysis, nucleus + -ar. Compare muscle and Latin mūsculus; muscular and mūsculāris.

Idioms1 entry

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