(1) Choice of words, especially with regard to correctness, clearness, or effectiveness. (2) Clarity of speech.

When your English teacher complains about some of the words you chose to use in an essay, she's talking about your diction. She may also use the term when commenting on the word choices made by a poet, and why a particular word was the best one possible in a particular line. But the second meaning of *diction* is just as common, and your English teacher might use that one on you as well, especially when she's asked you to read something aloud and you mumble your way through it.

(1) An official announcement that has the force of a law. (2) An order or command.

Edicts are few and far between in a democracy, since very few important laws can be made by a president or prime minister acting alone. But when a crisis arose in the Roman Republic, the senate would appoint a *dictator,* who would have the power to rule by edict. The idea was that the dictator could make decisions quickly, issuing his edicts faster than the senate could act. When the crisis was over, the edicts were canceled and the dictator usually retired from public life. Things are different today: dictators almost always install themselves in power, and they never give it up.

(1) The power or right to control or exercise authority. (2) The territory where power may be exercised.

Questions of jurisdiction are generally technical legal matters. The most important ones include which court will hear a given case and which law- enforcement agency can get involved. But although they may seem like mere technicalities, *jurisdictional* matters sometimes turn out to be all-important in the final outcome. Jurisdiction may depend on where you are (for example, in which state), on who you are (if you're a juvenile, for example, you may only be tried in juvenile court), and on what the subject is (for example, cases involving the estate left by someone who has died are dealt within probate court).

A formal and authoritative statement.

The word *dictum* is frequently used in philosophy, but also in economics, political science, and other fields. Almost any condensed piece of wisdom —”The perfect is the enemy of the good,” “Buy low, sell high,” “All politics is local,” etc.—can be called a dictum. In the law, judges may often add to a written opinion an *obiter dictum,* or “statement made in passing”—a strong statement that isn't directly relevant to the case being decided. If they're well thought out and eloquent, *obiter dicta* (notice the plural form) may be referred to by later judges and lawyers for years afterward.

(1) Having to do with the process of knowing, including awareness, judgment, and understanding. (2) Based on factual knowledge that has been or can be gained by experience.

Cognitive skills and knowledge involve the ability to acquire factual information, often the kind of knowledge that can easily be tested. So *cognition* should be distinguished from social, emotional, and creative development and ability. *Cognitive science* is a growing field of study that deals with human perception, thinking, and learning.

A person who believes that whether God exists is not known and probably cannot be known.

The words *agnostic* and *agnosticism* were coined around 1870 by the great English biologist T. H. Huxley, who had just spent a decade defending the works of Charles Darwin against the attacks of the church. Scientists often put a high value on evidence when arguing about religion, and many *agnostic* thinkers believe that human minds simply aren't equipped to grasp the nature of God. But agnostics differ from *atheists*, who actually claim that no God exists and may even think they can prove it. You may have seen the similar word *gnostic*, the name for followers of certain religious sects from around the time of Christ that sought spiritual knowledge and rejected the material world. An increasing interest in *gnosticism* today can be seen in the popular novels of Philip Pullman, Dan Brown, and Neil Gaiman.

In disguise, or with one's identity concealed.

In a famous myth, Zeus and Hermes visit a village incognito to test the villagers. The seemingly poor travelers are turned away from every household except that of Baucis and Philemon. This elderly couple, though very poor themselves, provide the disguised gods with a feast. When the gods finally reveal themselves, they reward the couple generously for their hospitality, but destroy the rest of the village.

(1) The chance of recovery from a given disease or condition. (2) A forecast or prophecy.

With its prefix *pro-*, meaning “before,” *prognosis* means basically “knowledge beforehand” of how a situation is likely to turn out. *Prognosis* was originally a strictly medical term, but it soon broadened to include predictions made by experts of all kinds. Thus, for example, economists are constantly offering prognoses (notice the irregular plural form) about where the economy is going, and climate scientists regularly *prognosticate* about how quickly the earth's atmosphere is warming.