A fever happens when the body's internal temperature is higher than normal. If you have a sore throat, a headache, and a fever, you may have the flu.

When you have a fever, your skin may feel hot, and your temperature as measured by a thermometer will be high. A fever can also make you feel achy, tired, and chilly, and it can be a sign that you've got some kind of infection. The Old English is fefor, from a Latin root, febris, also "fever." Doctors and nurses sometimes refer to a fever as a "febrile response."

Definitions of fever
  1. noun
    a rise in the temperature of the body; frequently a symptom of infection
    synonyms: febricity, febrility, feverishness, pyrexia
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    extremely high fever (especially in children)
    type of:
    (medicine) any sensation or change in bodily function that is experienced by a patient and is associated with a particular disease
  2. noun
    intense nervous anticipation
    “in a fever of resentment”
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    buck fever
    nervous excitement of an inexperienced hunter
    gold fever
    greed and the contagious excitement of a gold rush
    type of:
    anticipation, expectancy
    an expectation
Word Family

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