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addition

n.
US //əˈdɪʃən// UK //ɐdˈɪʃən// ad·di·tion
  1. 1 the act of adding (n.)
    B1 Intermediate

    the act of putting something extra with something else to make it larger or better.

    the process of joining or uniting one thing to another to increase the size, number, or importance of the whole.

    Example

    The addition of a new park has made the neighbourhood much more popular.

    Example

    The addition of fresh herbs at the very end of the cooking process preserves their delicate aroma and brightens the overall flavour profile.

    Usage

    Often used with the preposition 'of'.
  2. 2 a new person or thing (n.)
    B1 Intermediate

    a person or thing that is newly added to a group or place.

    a person or thing that is added to an existing group, collection, or structure.

    Example

    The baby is a wonderful new addition to their family.

    Example

    The latest addition to the museum's permanent collection is a rare landscape painting from the seventeenth century.

    Usage

    Commonly used in the phrase 'addition to'.
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  1. 3 maths operation (n.)
    A2 Elementary Math

    the process of calculating the total of two or more numbers.

    the arithmetic operation of summing two or more numbers or quantities.

    Example

    Children usually learn addition and subtraction before they try multiplication.

    Example

    The primary school curriculum focuses on mastering basic addition and subtraction before introducing more complex algebraic concepts.
  2. 4 chemical reaction (n.)
    C1 Advanced Technical Science

    a reaction where two or more molecules combine to form a larger one.

    an organic reaction in which two or more molecules combine to form a single larger product without the loss of any atoms.

    Example

    In this experiment, an addition reaction creates a new compound.

    Example

    The hydrogenation of ethene is a classic example of an addition reaction where hydrogen atoms bond to the carbon atoms of the double bond.
    • adduct formation
  3. 5 music notation (n.)
    C2 Proficiency Technical Music

    a small dot next to a musical note that makes it sound longer.

    a dot placed to the right of a note head to indicate that the duration of the note is to be increased by half.

    Example

    The addition of a dot to the half note means it lasts for three beats.

    Example

    The composer used rhythmic additions to create a sense of syncopation throughout the second movement of the sonata.
    • dotting
Origin

Etymology tree Proto-Indo-European *h₂éd Proto-Italic *ad Proto-Italic *ad- Latin ad- Proto-Indo-European *dʰeh₁- Proto-Indo-European *dʰéh₁tder. Proto-Italic *-ðō Latin -dō Latin addō Latin additiōder. Old French aditionder. Middle English addicioun English addition Sense of “what is added” dates from 14th century, from Middle English addicioun, addition, from Old French adition, from Latin additiōnem, accusative singular of additiō, from addō (“add, put”).

Word family
Idioms1 entry

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