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injection

n.
US //ˌɪnˈdʒɛkʃən// UK //ɪndʒˈɛkʃən// in·jec·tion
  1. 1 medical shot (n.)
    B1 Intermediate Medicine

    the act of putting medicine into your body using a needle and a syringe.

    the administration of a liquid medication or other substance into the body via a needle and syringe.

    Example

    The nurse gave him an injection in his arm to help with the pain.

    Example

    The patient required a subcutaneous injection of insulin twice daily to manage his blood sugar levels effectively.
  2. 2 financial boost (n.)
    B2 Upper Intermediate

    a large amount of money added to a business or project to help it succeed.

    the provision of a significant amount of capital to an organization to improve its financial health or support a specific project.

    Example

    The small company survived thanks to a cash injection from a new investor.

    Example

    The government announced a massive injection of funds into the public transport sector to modernize the aging rail infrastructure.
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  1. 3 fuel system (n.)
    B2 Upper Intermediate Technical

    the way fuel is forced into an engine to make it run.

    the pressurized introduction of fuel into the combustion chamber of an internal combustion engine.

    Example

    Modern cars use electronic fuel injection instead of old-fashioned carburetors.

    Example

    The mechanic explained that a fault in the fuel injection system was causing the engine to stall at high speeds.

  2. 4 computing/security (n.)
    C1 Advanced Technical Computing

    the act of putting extra code into a computer program, often to attack it.

    the exploitation of a computer bug by processing invalid data to change the course of execution, such as in a SQL injection attack.

    Example

    The website was hacked using a common technique called SQL injection.

    Example

    Developers must sanitize all user inputs to prevent malicious code injection that could compromise the database integrity.

  3. 5 mathematical function (n.)
    C1 Advanced Technical Math

    a rule where every starting value matches to a different result.

    a function that maps distinct elements of its domain to distinct elements of its codomain; a one-to-one mapping.

    Example

    In this math problem, we need to prove that the function is an injection.

    Example

    The student demonstrated that the mapping was an injection by showing that no two distinct inputs produced the same output value.
    • one to one function
Origin

Borrowed from Middle French injection, from Latin iniectio. The mathematical sense is from French injection, introduced by Nicolas Bourbaki in their treatise Éléments de mathématique. Equivalent to inject + -ion.

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