NEW YORK — Frum. Black-hat. Modern. Haredi Observant. Right-wing. Centrist. Ultra-Orthodox. Torah-true. Religious.

In a world where the choice between a black velvet yarmulke or a white knitted kippah is freighted with political meaning, the names differentiating sub-cultures of Orthodox Jews are loaded with symbolism.

The semiotics of being Orthodox have never been more complex. No representative of an Orthodox group likes what he or she is called in the press.

"I am just Orthodox," many say.

There are times, however, when distinctions have to be made. Finding terms that are free of judgments about a group's religiosity, but sufficiently descriptive to be widely understood, is a nearly impossible task.

The term "ultra-Orthodox," for example, does not sit well with Agudath Israel of America these days.

"`Ultra' means `too much,' and sends a message that we don't like, because we're not talking anymore about a far-right movement," said Rabbi Moshe Sherer, president of the organization. "This is a major stream in Jewish life."

"Haredi" is a term most people seem comfortable with in describing the Agudah constituency. It is a Hebrew word meaning "trembling," as in "trembling in awe of the Almighty."

Sherer does not mind the term "fervently Orthodox," which is used by the Jewish Telegraphic Agency, and also describes his movement as "uncompromising."

But those terms seem to indicate that everyone else is not fervent, or does compromise — ideas that do not sit well with the Centrist Orthodox.

The term "Modern Orthodox" has been used for decades. In the past 10 years, however, the term "Centrist" has begun to replace it, though not everyone is happy about it or even sure what it means.

As Orthodox Judaism's most conservative elements have grown in influence, they have succeeded to some extent in undermining the legitimacy of the Modern Orthodox philosophy.

That philosophy has long promoted the idea of living as an observant Jew in the larger culture, rather than encouraging segregation from it.

But now, some Modern Orthodox Jews have grown uneasy with the term "modern," feeling that it is too, well, modern.

And Orthodox Jews of every stripe are growing increasingly suspicious of anything smacking of modernity.

Yeshiva University's president, Norman Lamm, says that he introduced the term "centrist" to Orthodoxy. "I meant it not as a compromise between the Reform and the haredim, as some people think, but in the way that Maimonides speaks of the middle way," Lamm said.

"Centrist" has grown popular because people find the term modern "a bit haughty," he said.

Still, he said, "I wear the name `Modern Orthodox' as a badge of honor."

Lamm's preferred term, though, is "Torah U'Maddah Orthodoxy," which captures the essence of Y.U.'s philosophy — Torah combined with science, or secular studies.

But what to do when trying to define an Orthodox community, like that of the Young Israel synagogue movement, which falls somewhere in between the Agudah and Yeshiva University?

Rabbi Pesach Lerner, executive vice president of the National Council of Young Israel, describes a Young Israel member simply as "a Torah Jew."

He dislikes the word "centrist" because, he says, "What does it mean? That's the million-dollar question."

Then again, even the term "Orthodox" itself is a creation of the modern world. According to Lamm, it was first used by Reform Jews as they attempted to distinguish themselves from Jews who observe halachah (Jewish law). Some Reform Jews describe themselves as centrist, he said.

But no one, thus far, has volunteered to don the mantle of "leftist Orthodoxy."