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infection

n.
US //ˌɪnˈfɛkʃən// UK //ɪnfˈɛkʃən// in·fec·tion
  1. 1 the process of becoming sick (n.)
    B1 Intermediate Medicine

    the act of germs or bacteria entering a person's body and starting to grow.

    the process by which a pathogen invades a host organism and begins to multiply.

    Example

    The doctor cleaned the wound carefully to prevent an infection from starting.

    Example

    Public health officials focused on the primary infection route, which appeared to be contaminated water sources in the rural districts.

  2. 2 an illness (n.)
    B1 Intermediate Medicine

    a disease or sickness caused by bacteria, viruses, or other germs.

    a disease state resulting from the presence and activity of a pathogenic agent.

    Example

    She had a throat infection and had to stay home from work for three days.

    Example

    The patient was diagnosed with a secondary bacterial infection following a severe bout of seasonal influenza.

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  1. 3 physical signs of disease (n.)
    B2 Upper Intermediate Medicine

    a visible sign of a disease, such as redness or swelling around a cut.

    the physical manifestation or site of a pathogenic presence, often characterized by inflammation or suppuration.

    Example

    The nurse noticed a small infection around the stitches on his arm.

    Example

    The surgeon examined the site for signs of localized infection, noting the absence of redness or discharge during the follow-up appointment.

Origin

From Old French infection, from Late Latin īnfectiō. Equivalent to infect + -ion.

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