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noun compound pronunciation in British English /ˈkɒmpaʊnd/
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  1. 1
    [countable] chemistry a chemical substance that consists of two or more elements that together form a molecule. Each different compound has a fixed ratio of elements. For example the water compound (H2O) consists of two hydrogen atoms and one oxygen atom

    Why do chemical compounds behave as they do?

    Water is a compound of hydrogen and oxygen.

    1. a.
      [countable/uncountable] something that consists of two or more substances mixed together

      a herbal compound used for treating headaches

  2. 2
    [countable] a combination of things

    John and Steve working together? That’s a lethal compound.

  3. 3
    [countable] an enclosed area where a particular group of people live, or where people such as soldiers and prisoners can exercise
  4. 4
    [countable] linguistics a combination of two or more words that is used as a single word. The three different types of compound are noun compounds (for examplebus stop’), adjective compounds (for example ‘self-centred’), and verb compounds (for example to ‘wind-surf’).

sea lion

in an online conversation, repeatedly asking a person questions which suggest that you are interested in what they are talking about, but are actually intended to annoy them

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