fever

1 of 2

noun

fe·​ver ˈfē-vər How to pronounce fever (audio)
Synonyms of fevernext
1
a
: a rise of body temperature above the normal
b
: any of various diseases of which fever is a prominent symptom
2
a
: a state of heightened or intense emotion or activity
b
: a contagious usually transient enthusiasm : craze

fever

2 of 2

verb

fevered; fevering ˈfe-vər-iŋ How to pronounce fever (audio)
ˈfē-vriŋ

transitive verb

: to throw into a fever : agitate

intransitive verb

: to contract or be in a fever : become feverish

Examples of fever in a Sentence

Noun The symptoms of the disease include headache and fever. We waited in a fever of anticipation. He had us all in a fever with worry.
Recent Examples on the Web
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Noun
The first signs of infection are non-specific and include flu-like symptoms like fever, headaches, muscle pain, vomiting and sore throat. Michal Ruprecht, CNN Money, 30 Jan. 2026 The measles rash often starts on the face and spreads downward, with concomitant fevers spiking dangerously to 104°F or higher. Jesse Pines, Forbes.com, 30 Jan. 2026 Symptoms often include diarrhea, fever, stomach cramps and vomiting, typically appearing within six hours to six days after exposure, according to the CDC. Marley Malenfant, Austin American Statesman, 30 Jan. 2026 Healthy persons infected with salmonella often experience fever, diarrhea, nausea, vomiting, and abdominal pain. Michele Laufik, Martha Stewart, 30 Jan. 2026 See All Example Sentences for fever

Word History

Etymology

Noun

Middle English, from Old English fēfer, from Latin febris

First Known Use

Noun

before the 12th century, in the meaning defined at sense 1a

Verb

before the 12th century, in the meaning defined at intransitive sense

Time Traveler
The first known use of fever was before the 12th century

Cite this Entry

“Fever.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fever. Accessed 2 Feb. 2026.

Kids Definition

fever

noun
fe·​ver
ˈfē-vər
1
a
: a rise of body temperature above the normal
b
: a disease of which fever is an important symptom
2
: a state of excited emotion or activity

Medical Definition

fever

1 of 2 noun
fe·​ver ˈfē-vər How to pronounce fever (audio)
1
: a rise of body temperature above the normal whether a natural response (as to infection) or artificially induced for therapeutic reasons
2
: an abnormal bodily state characterized by increased production of heat, accelerated heart action and pulse, and systemic debility with weakness, loss of appetite, and thirst
3
: any of various diseases of which fever is a prominent symptom

fever

2 of 2 verb
fevered; fevering ˈfēv-(ə-)riŋ How to pronounce fever (audio)

transitive verb

: to affect with fever
the malarial plasmodia fevered him

intransitive verb

: to contract or be in a fever : be or become feverish
the malaria victim fevered intermittently

More from Merriam-Webster on fever

Last Updated: - Updated example sentences
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