Rage (often called fury or frenzy) is a feeling of intense, violent, or growing anger. It is sometimes associated with the fight-or-flight response, and is often activated in response to being in the presence of a threat. The phrase "thrown into a fit of rage" expresses the immediate nature of rage that occurs from extended exposure to a threat. If left unchecked, rage may lead to violence against the threat.
Old French raige, rage (French: rage), from Medieval Latin rabia, from Latin rabies ("anger fury"), akin to Sanskrit rabhas (violence). The Vulgar Latin spelling of the word possesses many cognates when translated into many of the modern Romance languages, such as Spanish, Galician, Catalan, Portuguese, and modern Italian: rabia, rabia, ràbia, raiva, and rabbia respectively.
Rage can sometimes lead to a state of mind where the individual experiencing it believes they can do, and often is capable of doing, things that may normally seem physically impossible. Those experiencing rage usually feel the effects of high adrenaline levels in the body. This increase in adrenal output raises the physical strength and endurance levels of the person and sharpens their senses, while dulling the sensation of pain. High levels of adrenaline actually impair memory. Temporal perspective is also affected: people in a rage have described experiencing events in slow-motion. Time dilation occurs due to the individual becoming hyper aware of the hind brain (the seat of fight or flight). Rational thought and reasoning would inhibit an individual from acting rapidly upon impulse. An older explanation of this "time dilation" effect is that instead of actually slowing our perception of time, high levels of adrenaline increase our ability to recall specific minutiae of an event after it occurs. Since humans gauge time based on the number of things they can remember, high-adrenaline events such as those experienced during periods of rage seem to unfold more slowly. It is safe to assume that there is truth in both theories.
A person in a state of rage may also lose much of their capacity for rational thought and reasoning, and may act, usually violently, on their impulses to the point that they may attack until they themselves have been incapacitated or the source of their rage has been destroyed. A person in rage may also experience tunnel vision, muffled hearing, increased heart rate, and hyperventilation. Their vision may also become "rose-tinted" (hence "seeing red"). They often focus only on the source of their anger. The large amounts of adrenaline and oxygen in the bloodstream may cause a person's extremities to shake. Psychiatrists consider rage to be at one end of the spectrum of anger, and annoyance to be at the other side.