What Does Running a Fever Mean?

Running a Fever Meaning

Definition: To have a fever; to have a body temperature that is too high due to illness.

Origin of Running a Fever

A synonymous expression is to run a temperature. Other ways to communicate this same idea include to have a fever, to have gotten a fever, and to have come down with a fever.

The scientific definition for running a fever is that a person’s internal body temperature has reached 100.4 degrees Fahrenheit, or 38 degrees Celsius.

Running a fever and running a temperature both originated around the late 1800s. However, running a temperature was more common until the 1970s, at which point running a fever became more prevalent.

Both expressions use run in the sense of moving upwards or increasing in amount.

Examples of Running a Fever

define running a feverIn the example below, a husband is worried about his wife.

Kip: Bye, honey! I’m heading off to work.

Caroline: Wait! I didn’t make your lunch yet. Just give me a minute.

Kip: Are you okay? You’re not usually in bed this late in the morning.

Caroline: I just feel a little dizzy and hot.

Kip: Wait a minute. I think you might be running a fever. Stay in bed while I take your temperature.

Caroline: I’m sure I’m fine.

Kip: Let’s let the thermometer decide that.

Caroline: If you insist.

running a fever originIn this second example, two lawyers are in court waiting for trial to start.

Jessica: You look sick. Are you about to pass out?

George: No, I’ll make it through the trial. I checked my temperature this morning, and I’m just running a little bit of a fever.

Jessica: You shouldn’t even be here if you have a fever. You could get me sick!

George: I know. I’m sorry about that but I didn’t want to jeopardize the trial!

More Examples

This excerpt is from an article about being careful when listening to doctors.

  • Having run an emergency room and working in a variety of health-care settings, Schwartz offers a warning to parents: Unless you or your child is close to being delirious or running a fever, avoid the ER and maybe even the doctor’s office as well. –USA Today

This excerpt is from an article about religions that prohibit accepting medical care.

  • On March 30, 2011, Sevy’s 14-year-old son Rockwell was reported dead after having been ill for “about two weeks,” according to DeGeus-Morris’ report. He had been running a fever and experiencing difficulty breathing, the report said, and died in his mother’s lap. –LA Times


The phrase running a fever means having an elevated body temperature because one is sick.