The blog and resource site Religious Right Watch has a glossary and discussions of some basic terms central to any serious discussion of the Religious Right, and includes helpful links to Wikipedia and authoratative online sources.

For example, a definition of religious right:

Religious Right A broad, varied collection of political movements of religious and social conservatives arising in the 1970's, and overwhelmingly American and Christian to the point of rendering the descriptions "Religious Right" and "Christian Right" effectively synonymous. (See: "Christian Right.") <christian_right.htm> However, the Religious Right can be said to exist comparatively weakly in nations other than the United States, including Canada and the United Kingdom, and to include individuals and movements informed by Judaism, Islam, Mormonism, and other faith traditions besides Christianity. In the United States, it is closely associated with the Republican Party. The vast majority of members of the Christian Right insist that the United States was founded as a Christian nation. (see AU.org Is America a 'Christian Nation'?")  

usage. Also "religious right."

"Proponents of using the term Religious Right argue that in addition to Christians, there are conservative Jews and Muslims active in a broad coalition. Opponents argue that Christians vastly outnumber Jews and Muslims in this coalition, and that using the term Religious Right masks this fact." (Wikipedia "religious right")

note. Not all religious conservatives are political conservatives; not all religious conservatives are members of the Religious Right.

Political Research Associates, a Somerville, Massachusetts-based think tank that studies rightwing movements, has a glossary  of terms that are used in the course of studying the broad, multifaceted right, including the religious right.

Here are some examples:  

Eschatology: The idea that there is an "end time" for the current historic epoch at which point the forces of evil will be vanquished and the forces for good rewarded. In Christianity, the study of Biblical prophesy regarding the end times.

Extremist: The term "extremist" is of dubious value and should be avoided used As sociologist Jerome Himmelstein argues, "At best this characterization tells us nothing substantive about the people it labels; at worst it paints a false picture. " (1998: 7).

Millennialism: A sense of expectation that a significant epochal transformation is imminent, marking either the end of a thousand year period, or signal its beginning, or both. Two major forms of millennialist response are passive waiting versus activist intervention. Can involve varying degres of apocalypticism. In Christianity, the idea that the Second Coming of Christ marks a thousand year period.

Millennialist variations in Christianity include:

--Pre-millennialism - Belief that Christ returns at the beginning of a thousand year period of peace and prosperity. Can foster passivity or intervention.

--Post-millennialism - Belief that Christ returns only after a thousand years of reign and rule by godly Christian men. Fosters intervention. See Reconstructionism.

--A-millennialism - Belief that Christ's eventual return cannot be anticipated, thus de-emphasizing it as a practical immediate consideration. Most a-millennialists believe that Christ's return ends history.

--Preterism - Belief that most or all of the millennium mentioned in Revelation and other books of the Bible already has occurred.

Reconstructionism: The most militant form of Protestant dominionism, arguing that the US Constitution is merely a codicil to Christian Biblical law. Rooted in Calvinist theonomy and the idea of America as a Christian redeemer nation. Sees religion, culture, and nation as an integral unit. A form of Christian nationalism, Reconstructionism echoes of the European clerical fascist movements of the 1930s. A post-millennial view urging militant Christian intervention in secular society since faithful men must reign and rule for a thousand years before Christ returns. Has no connection whatsoever with Jewish Reconstructionism.

And mainstream journalism is also tackling definitions and useage in a new online stylebook.

The Religion Newswriters Association, an organzation of professional journalists, has recently posted an online stylebook similar to those published by the Associated Press and The New York Times. It focuses on simple definitions and useage, and sometimes delves into thumnail history.

Religion Newswriters' Religion Stylebook is an easy-to-use, authoritative guide created for journalists who report on religion in the mainstream media. In it, you'll find:

Entries on the major religions, denominations, and religious organizations that journalists encounter in daily reporting;

Preferred spellings, capitalizations, and usage guidelines for religious terms, along with definitions;

Accurate titles for religious leaders in different traditions;
Pronunciation guides;

Entries on terms used in stories on current topics in the news, including abortion, homosexuality, church/state issues and intelligent design;
Entries on religion terms that are not included in The Associated Press Stylebook. The Religion Stylebook generally follows AP style but includes many terms it does not cover.

Here are a few examples:

faith-based: Term that came into popular use when President George W. Bush established the White House Office of Faith-Based and Community Initiatives in 2001. Generally, the adjective faith alone is preferred, as in faith groups instead of faith-based groups.

fundamentalism, fundamentalist: A Christian religious movement that began in the U.S. in the late 19th century and early 20th century to counter liberalism and secularism. It emphasized the inerrancy of the Bible. In recent years, fundamentalist and fundamentalism have become associated with any religious reactionary movement, such as Islamic fundamentalism. The words also have been used as pejoratives. Journalists often, and erroneously, label all conservative Christians, including conservative evangelicals, as fundamentalists. It is best to avoid the words unless a group applies the term to itself.

evangelical: By definition, all Christians are evangelicals. The word evangelical is derived from the Greek evangelion, which means "good news" or "gospel." But the term evangelical has generally come to mean Protestants who emphasize personal conversion; evangelism; the authority, primacy -- and, usually -- inerrancy of the Bible; and the belief that Jesus' death reconciled God and humans. Evangelicals tend to be conservative theologically, but the terms evangelical and conservative Christian are not synonymous, though they both may apply to the same people. Fundamentalists, who generally separate themselves from what they see as a sinful culture, are distinct from evangelicals, who tend to embrace culture and use it to build up the church. In the early 21st century, religious identification surveys show that between a quarter and 40 percent of the U.S. population claims the evangelical label. Many, though not all, also identify with a specific tradition or denomination, ranging from mainline Protestant denominations to the Roman Catholic Church. In Europe evangelical is a generic word for Protestants. Uppercase only when part of a formal name.

Since it is a work in progress and serves mainstream journalism, it is interesting to note what is not included, as well as what is.

I find that so far, it is helpful for definitions and useage of basic terms like menorah, non-denominational, or National Council of Churches, but it does not go into the major theological terms or factions with political implications, such as Premillenialism and Postmillenialism; Christian nationalism, Christian Idenitity, liberation theology, Christian Zionism, dominionism and Christian Reconstructionism.  Although there are discussions of the terms gay and lesbian, there is no mention of for example, of "reparative therapy" or "conversion therapy" the controversial notion that Christian conversion and counseling of a certain sort, can cure homosexuality,and is often in the news. (Then again, the other glossaries have not gotten to that one either although the Wikipedia, always a useful reference, has.)  There is a detailed definition for Opus Dei and its relation to The DaVinci Code, but there is no mention of Tim LaHaye and the Left Behind series of novels, movies and the video game. There are no definitions of secular, humanism, or secular humanism. And although elements of the story are reported by religion writers all the time, there is no defitition of the controversial rightwing "renewal groups," in mainline churches, and the group driving them -- the Institute on Religion and Democracy.  The terms theocracy, theocratic, and theonomy, have so far gone undefined, although they stand at the center of contemporary writing about religion and public affairs in the U.S. and internationally.  As a work in progress the Religion Newswriters Association invites comments and suggestions.

These online glossaries, each with their different emphases, are valuable tools for anyone seeking to write, speak and think clearly about the religious right, and religion and politics in general.