Heat is energy in transfer to or from a thermodynamic system by mechanisms other than thermodynamic work or transfer of matter.
Heat or HEAT may also refer to:
Medicine
- Fever, a body temperature above the normal range in response to internal physiological conditions
- Heat illness, a spectrum of disorders due to environmental exposure to heat:
- Heat cramps, muscle spasms that result from loss of large amount of salt and water through exercise
- Heat edema, swelling of the hands and/or feet due to over-expansion of the blood vessels in the extremities in response to heat
- Heat exhaustion, caused by the loss of water and electrolytes through sweating
- Heat rash, skin irritations caused by excessive sweating or blocked sweat glands
- Heat stroke, with a body temperature greater than 40.6 °C (105.1 °F)
- Heat syncope, fainting or dizziness as a result of overheating
- Heat tetany, cramps and seizures caused by calcium and/or magnesium loss due to excessive sweating in short periods of stress in high heat
- Hyperthermia, elevated body temperature due to failed thermoregulation that occurs when a body produces or absorbs more heat than it dissipates
- Malignant hyperthermia, a type of severe reaction that may occur to susceptible patients during general anesthesia
- Hot flash or hot flush, a feeling of heat, with sweating and increased heart rate, usually experienced by menopausal women due to low estradiol
Films
- Heat (1963 film), a Soviet drama film directed by Larisa Shepitko
- Heat (1972 film), an American drama film directed by Paul Morrissey, starring Sylvia Miles and Joe Dallesandro
- Heat (1986 film), an American action-thriller film directed by Dick Richards and Jerry Jameson, starring Burt Reynolds
- Heat (1995 film), an American crime drama directed by Michael Mann, starring Al Pacino, Robert De Niro and Val Kilmer
- Natural Justice: Heat (1996), an Australian television film, sometimes referred to as Heat, directed by Scott Hartford-Davis
- Heat (2006 film), a Russian comedy film directed Rezo Gigineishvili
- The Heat (film), a 2013 comedy film directed by Paul Feig, starring Sandra Bullock and Melissa McCarthy
- Pungency or piquantness ("Heat" or "hotness"), the spiciness of foods such as black pepper, chili peppers, garlic and onions, ginger, mustard, and horseradish
- Heat, the traditional and most common means of cooking food
- Heat, applied post-preparation to food with a heat lamp, to prevent the growth of microorganisms before the food is consumed
- Heat, a preliminary race or match in a sports tournament
- Fastball (colloquialism: heat), in baseball