To make impossible beforehand; prevent.

*Preclude* is often used in legal writing, where it usually refers to making something legally impossible. A new law may be passed by Congress to preclude any suits of a certain kind against a federal agency, for example. Some judges have found that the warnings on cigarette packs preclude any suits against the tobacco companies by lung-cancer sufferers. But there are plenty of nonlegal uses as well. Bad weather often precludes trips to the beach, and a lack of cash might preclude any beach vacation at all.

Showing the qualities or abilities of an adult at an unusually early age.

Growing from a child to an adult is like the slow ripening of fruit, and that's the image that gave us *precocious.* The word is based on the Latin verb *coquere,* meaning “to ripen” or “to cook,” but it comes most directly from the adjective *praecox,* which means “ripening early or before its time.” *Precocity* can occasionally be annoying; but precocious children don't come precooked, only “preripened.”

(1) To influence in advance in order to create a particular attitude. (2) To make one more likely to develop a particular disease or physical condition.

*Predispose* usually means putting someone in a frame of mind to be willing to do something. So a longtime belief in the essential goodness of people, for example, will predispose us to trust a stranger. Teachers know that coming from a stable family generally predisposes children to learn. And viewing television violence for years may leave young people with a *predisposition* to accept real violence as normal. The medical sense of the word is similar. Thus, a person's genes may predispose her to diabetes or arthritis, and malnutrition over a long period can predispose you to all kinds of infections.

Something that is required in advance to achieve a goal or to carry out a function.

*Prerequisite* is partly based on *requirere,* the Latin verb meaning “to need or require.” So a prerequisite can be anything that must be accomplished or acquired before something else can be done. Possessing a valid credit card is a prerequisite for renting a car. A physical exam may be a prerequisite for receiving a life-insurance policy. And successful completion of an introductory course is often a prerequisite for enrolling in a higher-level course.

To restate the meaning (of something written or spoken) in different words.

When we paraphrase, we provide a version that can exist beside the original (rather than replace it). We paraphrase all the time. When you tell a friend what someone else has said, you're almost always paraphrasing, since you're not repeating the exact words. If you go to hear a talk, you might paraphrase the speaker's main points afterward for your friends. And when writing a paper on a short story, you might start off your essay with a *paraphrase* of the plot. Paraphrasing is especially useful when dealing with poetry, since poetic language is often difficult and poems may have meanings that are hard to pin down.

Of, relating to, or being a trained assistant to a lawyer.

Much of the work in a law office can be done by paralegal assistants, also called legal aides or simply *paralegals*, who work alongside licensed lawyers. Often a paralegal is trained in a narrow field and then entrusted with it. In this respect, paralegals are similar to *paraprofessionals* in other fields, such as engineering. Paraprofessionals used to be trained in the office itself, but today it's common to study for a paraprofessional certificate or degree at a community college or university.

In ground warfare, wounded troops must usually be transported from the front lines back to field hospitals, and trained *paramedical* personnel—that is, nondoctors, usually known as *medics* or *corpsmen*—were first widely used in such situations. It took many decades for the wartime model to be applied effectively to ordinary peacetime medicine. With advances in medical technology (such as defibrillators, for restarting a heart after a heart attack), paramedics became an essential part of emergency medicine, and today hundreds of thousands of people owe their lives to paramedics. *Paraprofessionals* who work only in hospitals and clinics usually go by other titles.

Relating to a force formed on a military pattern, especially as a possible backup military force.

This term *paramilitary* can take in a wide range of organizations, but is usually applied to forces formed by a government. Groups opposing a government, even when organized along military lines, are more often referred to as guerrillas or insurgents. In countries with weak central governments (such as, in recent times, Afghanistan, Somalia, Iraq, or Congo), warlords may form their own paramilitary forces and take over all local police and military functions. *Paramilitary* often has a sinister sound today, since it's also applied to groups of off-duty military or police personnel who carry out illegal violence, often at night, with the quiet support of a government.