(1) Something that protects or defends; shield. (2) Sponsorship or guidance by an individual or organization.

The original aegis was a goatskin shield or breastplate, symbolizing majesty, that was worn by Zeus and his daughter Athena in Greek mythology. Athena's aegis bore the severed head of the monstrous Medusa. *Aegis* came to be used for any kind of invulnerable shield. But today we almost always use the word in the phrase “under the aegis of . . . ,” which means “under the authority, sponsorship, or control of.”

(1) An extraordinary gift for leadership that attracts popular support and enthusiasm. (2) A special ability to attract or charm; magnetism.

*Charisma* is Greek for “gift,” but its traditional meaning comes from Christian belief, where it originally referred to an extraordinary power—the gift of healing, the gift of tongues, or the gift of prophecy—bestowed on an individual by the Holy Spirit. The first nonreligious use of *charisma* didn't appear until the 20th century, when it was applied to that mysterious personal magnetism that a lucky few seem to possess, especially the magnetism with which a political leader can arouse great popular enthusiasm. When John F. Kennedy was elected president in 1960, its use by journalists popularized the term in the mass media. Since then, actors, rock stars, athletes, generals, and entrepreneurs have all been said to possess charisma.

(1) A sense of confidence and satisfaction in oneself; self-esteem. (2) An exaggerated sense of self-importance.

*Ego* is the Latin word for “I.“ So if a person seems to begin every sentence with “I,” it's sometimes a sign of a big ego. It was the psychologist Sigmund Freud (well, actually his original translator) who put *ego* into the popular vocabulary, but what he meant by the word is complex, so only other psychologists really use it in the Freudian sense. The rest of us generally use *ego* simply to mean one's sense of self-worth, whether exaggerated or not. When used in the “exaggerated” sense, *ego* is almost the same thing as *conceit.* Meeting a superstar athlete without a trace of this kind of ego would be a most refreshing experience. But having a reasonable sense of your own worth is no sin. Life's little everyday victories are good—in fact, necessary— for a healthy ego.

The features, attitudes, moral code, or basic beliefs that define a person, a group, or an institution.

*Ethos* means “custom” or “character” in Greek. As originally used by Aristotle, it referred to a man's character or personality, especially in its balance between passion and caution. Today *ethos* is used to refer to the practices or values that distinguish one person, organization, or society from others. So we often hear of the ethos of rugged individualism and self- sufficiency on the American frontier in the 19th century; and a critic might complain about, for example, the ethos of violence in the inner cities or the ethos of permissiveness in the suburbs.

Unreasonable or unjustified pride or self-confidence.

To the Greeks, *hubris* referred to extreme pride, especially pride and ambition so great that they offend the gods and lead to one's downfall. Hubris was a character flaw often seen in the heroes of classical Greek tragedy, including Oedipus and Achilles. The familiar old saying “Pride goeth before a fall” is basically talking about hubris.

The part of a person's unconscious mind that relates to basic needs and desires.

In Latin, *id* means simply “it.” Sigmund Freud (and his translator) brought the word into the modern vocabulary as the name of what Freud believed to be one of the three basic elements of the human personality, the other two being the *ego* (see ego) and the *superego*. According to Freud, the id is the first of these to develop, and is the home of the body's basic instincts, particularly those involving sex and aggression. Since the id lacks logic, reason, or even organization, it can contain conflicting impulses. Primitive in nature, it wants to be satisfied immediately. Although its workings are completely unconscious, Freud believed that its contents could be revealed in works of art, in slips of the tongue (“Freudian slips”), and in one's dreams.

(1) Sexual drive. (2) In psychoanalytic theory, energy that is derived from primitive biological urges and is usually goal-oriented.

The Latin word *libido,* meaning “desire, lust,” was borrowed by Sigmund Freud as the name for a concept in his own theories. At first he defined *libido* to mean the instinctual energy associated with the sex drive. Later he broadened the word's meaning and began using it to mean the mental energy behind purposeful human activity of any kind; in other words, the libido (for which Freud also used the term *eros,* a Greek word meaning “sexual love”) came to be regarded as the life instinct, which included sex along with all the other impulses we rely on to keep us alive. But those of us who aren't psychologists use the word simply as a synonym for “sex drive.”

(1) A serious injury to the body. (2) An abnormal psychological state caused by mental or emotional stress or physical injury.

*Trauma* is the Greek word for “wound.” Although the Greeks used the term only for physical injuries, nowadays *trauma* is just as likely to refer to emotional wounds. We now know that a *traumatic* event can leave psychological symptoms long after any physical injuries have healed. The psychological reaction to emotional trauma now has an established name: *post-traumatic stress disorder,* or PTSD. It usually occurs after an extremely stressful event, such as wartime combat, a natural disaster, or sexual or physical abuse; its symptoms include depression, anxiety, flashbacks, and recurring nightmares.