The internal temperature of the human body, usually about 37ºC.
Level of heat produced and sustained by body processes. In adults, oral (taken by mouth) temperatures range from 96° to 99°F, with 98.6°F generally being regarded as normal; axillary (armpit) temperatures are typically lower, rectal temperatures higher. Body temperature normally varies during the day, depending on the level of activity, ambient temperature, and other factors; the normal range is greater for children than for adults. Marked changes in body temperature (e.g., fever) are generally indicative of disease.
The intensity of heat of the body, as measured by a thermometer. Body temperature is accurately controlled by a small area at the base of the brain (the hypothalamus); in normal individuals it is maintained at about 37°C (98.4°F). Heat production by the body arises as the result of vital activities (e.g. respiration, heart beat, circulation, secretion) and from the muscular effort of exercise and shivering. A rise in body temperature occurs in fever.
The temperature of the body, an indicator of health and disease and one of the vital signs. Body temperature varies with the time of day and the site of measurement. Oral temperature is usually 97.5° to 99.5°F (36° to 38°C). Daily fluctuations in an individual may be 1° or 2°F. Body temperature may be measured by a placing a thermometer in the mouth, the rectum, under the arm, in the bladder, within the chambers of the heart, or in the external auditory canal of the ear. Rectal temperature is usually from 0.5° to 1.0°F (0.28° to 0.56°C) higher than by mouth; axillary temperature is about 0.5°F (0.28°C) lower than by mouth. Oral temperature measurement may be inaccurate if performed just after the patient has ingested cold substances or has been breathing with the mouth open.
The temperature of the body. Temperatures may be classified as: normal, 98°-99°F.; subnormal, below 98°F.; collapse, below 96°F.; febrile, above 99°F.; and hyperpyrexia, above 107°F. Pyrexia is a state of having a continuously high temperature coupled with thirst, headache, and a rapid pulse. The three principal types of fever accompanied by temperature are: continued fever or continued temperature, when the fever does not fluctuate more than about 1½°F. during 24 hours and at no time touches the normal; remittent fever or remittent temperature, when the daily fluctuations exceed 2°; and intermittent fever or intermittent temperature, when the fever is only present for several hours during the day. In many cases the temperature may be up in the morning and normal at night, or vice versa. Thus it is important to take the patient’s temperature morning, afternoon, and evening before one can be certain that it has come down to normal properly. No patient should be allowed out of bed until the temperature has been normal or below normal morning, afternoon, and evening of one day and is still normal or below normal the following morning.