fever

American  

[fee-ver] / ˈfi vər /

noun

fevers plural

1. an abnormal condition of the body, characterized by undue rise in temperature, quickening of the pulse, and disturbance of various body functions.

2. an abnormally high body temperature.

3. the number of degrees of such a temperature above the normal.

4. any of a group of diseases in which high temperature is a prominent symptom.

   scarlet fever.

5. intense nervous excitement.

   The audience was in a fever of anticipation.

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verb (used with object)

1. to affect with or as with fever.

   The excitement fevered him.

fever British  

/ ˈfiːvə /

noun

1. an abnormally high body temperature, accompanied by a fast pulse rate, dry skin, etc

2. any of various diseases, such as yellow fever or scarlet fever, characterized by a high temperature

3. intense nervous excitement or agitation

   she was in a fever about her party

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verb

1. (tr) to affect with or as if with fever

fever Scientific  

/ fē′vər /

1. A body temperature that is higher than normal. Fever is the body's natural response to the release of substances called pyrogens by infectious agents such as bacteria and viruses. The pyrogens stimulate the hypothalamus in the brain to conserve heat and increase the basal metabolic rate.

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fever Idioms  

1. see cabin fever; run a fever.

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Other Word Forms

Derived Forms

• fevered
  adjective
• feverless
  adjective
• unfevered
  adjective

Inflected Forms

Nouns

• fevers
  plural

Etymology

Origin of fever

First recorded before 1000; Middle English; Old English fefer, from Latin febr-, stem of febris; reinforced by Anglo-French fevre, Old French fievre, from Latin, as above

Explanation

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."

Example Sentences

See Examples For:

fever fevers

As the number of reported infections continued to rise and fears over our favorite seasonal eats reached a fever pitch, the exact source of the outbreak remained a mystery.

From Salon ● Jul. 25, 2026

Most cases are mild and amount to little more than a cough, fever, and runny nose.

From Slate ● Jul. 24, 2026

For those who do, the most common symptoms include high fever, headache, muscle and joint pains, nausea and rashes.

From BBC ● Jul. 23, 2026

Others will experience mild symptoms such as fever, body aches and nausea.

From Los Angeles Times ● Jul. 13, 2026

The fever sent me into a trancelike state in which I didn’t even wish to recover.

From "Flying Through Water" by Mamle Wolo

It is considered the safest option for treating pain and fever in pregnant women, as other medications, including aspirin or ibuprofen, present proven risks to the fetus -- as do untreated fevers.

From Barron's ● Jul. 13, 2026

They are also looking at a vaccine for viral haemorrhagic fevers, which would include Ebola species.

From BBC ● Jun. 4, 2026

Health officials say the sick passengers have symptoms like fevers along with gastrointestinal and respiratory issues.

From MarketWatch ● May 5, 2026

FDA chief Marty Makary explained that acetaminophen is the only approved over-the-counter drug to treat high fevers in pregnancy that can damage a fetus, and that “the choice still belongs with parents.”

From The Wall Street Journal ● Oct. 29, 2025

I find pediatric sick-visit reports for rashes, allergies, eczema, colds, fevers, and two ear infections, all before I was four months old.

From "Everything, Everything" by Nicola Yoon

Related Words

• delirium
• frenzy
• turmoil