The state of being equal.

*Parity* has special meanings in such fields as physics, math, medicine, genetics, and marketing. Back when the Soviet Union and the U.S. were opposing superpowers, there was often talk of parity in nuclear weapons between the two sides. We sometimes hear about parity between mental and physical health in insurance coverage, or parity in colleges' funding of men's and women's athletics. But parity may be most common in discussions of currencies. The *exchange rate* between two national currencies often changes every day, as each drifts higher or lower, and occasionally two similar currencies, such as the euro and the U.S. dollar, will achieve parity, but it rarely lasts long.

A noticeable and often unfair difference between people or things.

*Disparity* contains the Latin *dis*, meaning “apart” or “non-” (see DIS), so a disparity is a kind of “nonequality.” The word is often used to describe a social or economic condition that's considered unfairly unequal: a racial disparity in hiring, a health disparity between the rich and the poor, an income disparity between men and women, and so on. Its adjective, *disparate* (accented on the first syllable), is often used to emphasize strong differences.

Someone or something of unequaled excellence.

American children learn this word (even if they can't pronounce it) as the name of the candies covered with white sugar pellets that they buy at the movie theater, and it's also the name of the pellets themselves. But the more general meaning is common too. *Nonpareil* is also an adjective. A famous boxing champion of the 1920s was known as Nonpareil Jack Dempsey, when he wasn't being called “the Manassa Mauler.” Like its synonyms *paragon* and *peerless*, *nonpareil* is popular as a company and product name; it's also the name of a fruit, an almond, a bird, and a butterfly.

Below a usual or normal level.

Since *sub-* means “below” (see SUB), almost anything that fails to measure up to a traditional standard may be called subpar. So you may hear of subpar ratings for a TV show, subpar care at a nursing home, subpar attendance at a concert, or subpar work by a contractor. If you played a subpar round of golf, though, you needed *more* strokes than you should have.

Fearful of heights.

The Greek *akron* means “height” or “summit,” and the *acro-* root can be seen in such words as *acrobat* and *Acropolis*. Almost everyone has some fear of heights, but an abnormal dread of high places, along with the vertigo (dizziness) that most *acrophobes* also experience, are common as well; in fact, *acrophobia* is one of the half-dozen most common recognized phobias. Acrophobia and claustrophobia both play a role in another well-known phobia: the fear of flying, itself often known as *aerophobia*.

A fear of being in embarrassing or inescapable situations, especially in open or public places.

The *agora* was the marketplace in ancient Greece; thus, agoraphobia often involves fear of public places and crowds. But it also may involve fear of being in shops, or even fear of being in open spaces, or fear of traveling alone. It may also be a fear of experiencing some uncontrollable or embarrassing event (like fainting) in the presence of others with no help available. Agoraphobia can be hard to understand for those who don't suffer from it, especially because it can take so many different forms, but it is often a serious and socially crippling condition.

One who has a fear or hatred of strangers or foreigners.

*Xenophobe* is partly based on the Greek noun *xenos*, meaning “stranger, guest, foreigner.” Unlike other phobias, *xenophobia* isn't really considered an abnormal condition; instead, it's generally thought of as just serious narrow- mindedness, the kind of thinking that goes along with racism and extreme patriotism. In times of war, a government will often actually try to turn all its citizens into xenophobes.

Having a fear or dislike of spiders.

In Greek mythology, Arachne was a weaver of such skill that she dared to challenge the goddess Athena at her craft. When she won their competition by weaving a tapestry disrespectful to the gods, the enraged Athena tore it to shreds, and in despair Arachne hanged herself. Out of pity, Athena loosened the rope, which became a cobweb, and changed Arachne into a spider. Today, the spiders, scorpions, mites, and ticks all belong to the class known as *arachnids*. Arachnophobia is the most common of the animal phobias; but many people suffer from similar phobias regarding snakes *(ophidiophobia)*, dogs *(cynophobia)*, and mice and rats *(musophobia)*.