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chaos

n.
US //ˈkeɪɑs// UK //kˈeɪɒs// chaos
  1. 1 total confusion (n.)
    B2 Upper Intermediate

    a situation where everything is happening at once and there is no order.

    a state of utter confusion or disorder; a total lack of organization or predictability.

    Example

    The station was in total chaos after all the trains were cancelled.

    Example

    The sudden withdrawal of funding threw the entire research department into a state of chaos, leaving dozens of projects unfinished.

  2. 2 complex systems (n.)
    C1 Advanced Technical Science

    a type of math or science where very small changes can lead to huge, unpredictable results.

    the property of a complex system where small variations in initial conditions result in massive differences in later states.

    Example

    Weather is a great example of chaos because a tiny change in wind can change a whole storm.

    Example

    In mathematics, chaos describes systems that appear random but are actually governed by sensitive, non-linear laws.

    Usage

    Often used in the phrase 'chaos theory'.

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  1. 3 mythology (n.)
    C2 Proficiency Literary Academic Religion

    the empty space or confusion that existed before the world was created in ancient stories.

    the primordial void or state of matter preceding the creation of the universe in various cosmogonies.

    Example

    In ancient Greek myths, the universe began as a dark chaos.

    Example

    The poet describes the transition from primordial chaos to the structured harmony of the heavens.

Origin

Learned borrowing from Ancient Greek χάος (kháos, “vast chasm, void”). Doublet of gas, which was borrowed through Dutch. In Early Modern English, used in the sense of the original Greek word. In the meaning "primordial matter" from the 16th century. Figurative usage in the sense "confusion, disorder" from the 17th century. The technical sense in mathematics and science dates from the 1960s.

Word family

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