A person who opposes or is unfriendly toward another; an opponent.

On the stage or screen, in a story or a novel, the *protagonist* is the main character and the antagonist is the opposing one. *Pro-* and *ant-* usually mark the good and bad characters, but not always; there may occasionally be an evil protagonist and a good antagonist. In the drama of the real world, it's especially hard to sort out which is which, so we usually speak of both parties to a conflict as antagonists. During a strike, for example, representatives of labor and management become antagonists; they often manage to *antagonize* each other, and the *antagonism* often remains after the strike is over.

An *antibody* is a protein produced by your immune system to fight outside invaders. Since the enemy substance actually triggers the production of antibodies, such substances are called antigens—*anti-* being short for *antibody*, and *-gen* meaning “producer.” (In a similar way, an *allergen* produces an allergy, and a *pathogen* produces a pathology or disease.) Antigens are often rodlike structures that stick out from the surface of an invading organism—usually a bacterium or a virus—and allow it to attach itself to cells in the invaded body. But unfortunately for them, in doing so they let the immune system know they're present, and the body is flooded with an army of Pac-Man-like antibodies.

A strong dislike.

When the nation of Yugoslavia was created in 1945, it combined a number of ethnic groups with a history of violent antipathy toward each other. In 1991– 92 four regions of the country announced that they would become independent nations; a bloody six-year war followed, fueled by these ancient and powerful antipathies. The American Civil War similarly resulted from antipathy between the North and the South. But in the U.S.'s relations with its next-door neighbors, it's been a long time since emotions have gotten much stronger than annoyance.

(1) The contrast or opposition of ideas. (2) The exact opposite.

Writers and speechmakers use the traditional pattern known as antithesis for its resounding effect; John Kennedy's famous “ask not what your country can do for you—ask what you can do for your country” is an example. But *antithesis* normally means simply “opposite.” Thus, war is the antithesis of peace, wealth is the antithesis of poverty, and love is the antithesis of hate. Holding two *antithetical* ideas in one's head at the same time—for example, that you're the sole master of your fate but also the helpless victim of your terrible upbringing—is so common as to be almost normal.

Goods that are forbidden by law to be owned or brought into or out of a country; smuggled goods.

In Latin a *bannus* was an order or decree, so a *contrabannum* was something that went against a decree. This led to the Italian word *contrabbando,* from which we get *contraband.* Contraband items aren't always illegal; they may simply be things (such as cigarettes) that are meant to be taxed. So a dealer in untaxed contraband can charge a little less and still make enormous profits. Of course, if the item is actually forbidden, like illegal drugs, then the profits could be much greater.

Something (such as a symptom or condition) that makes a particular treatment, medication, or procedure likely to be unsafe.

For doctors, an *indication* is a symptom or circumstance that makes a particular medical treatment desirable. Serious anxiety, for example, is often an indication for prescribing a tranquilizer. A contraindication, then, is a symptom or condition that makes a treatment risky, such as taking certain other medications at the same time. Drugs and conditions that are *contraindicated* for a medication are listed on its label, and reeled off at high speed in TV ads. Patients can guard against the dangers of drug interaction by reading labels carefully and making sure their doctors know what else they're currently taking.

(1) To go against or act contrary to; to violate. (2) To oppose in an argument, to contradict.

*Contravene* is most often used in reference to laws. So a government may take a company to court claiming that its policies are in *contravention* of national labor laws. The contravention of copyright laws is a big topic today especially where electronic information is involved. And a country might be punished if a trade organization finds that it's contravening international trade agreements.

Anyone who thinks that most of what the public believes is wrong would be called a contrarian. And *contrarian* is a basic term in the vocabulary of investing. In fact, most successful investors often behave like contrarians by “buying low and selling high”—that is, buying stocks that are cheap because most investors put a low value on them but that have the possibility of rising, and selling stocks that most investors are valuing highly but that seem likely to decline. The word may be most common as an adjective; so you may express a *contrarian* opinion, hold a contrarian view, or pursue a contrarian investment strategy.