The short answer is that “ordinarian” is not a common or standard English word. If you have seen it or heard it, it is very likely a mix-up, a mistaken spelling, or an informal invention based on more established terms.

In most cases, people who ask about “ordinarian” are actually looking for one of three related ideas.

The church meaning you might be reaching for

In Catholic and some other Christian contexts, the correct term is usually ordinary. An ordinary is a person who holds a specific kind of authority over a church jurisdiction. This meaning is specialized and different from the everyday sense of the word “ordinary.”

So if your context was religious leadership or church governance, the word you probably want is ordinary, not “ordinarian.”

The structure that sounds similar

Another closely related term is ordinariate. An ordinariate is a type of church jurisdiction, similar in some ways to a diocese. In some cases it is organized around a community or tradition rather than a strict geographic region.

If you were reading about a specific church body or community and encountered unfamiliar terminology, “ordinarian” may have been a mistaken interpretation of “ordinariate” or a casual way someone tried to describe membership in one.

The everyday meaning that tempts an invented word

Outside of religion, some people might use “ordinarian” to mean “a very ordinary person.” But standard English would simply say an ordinary person.

This is a good example of how English speakers sometimes create words that feel logical, even if they are not widely accepted.

A quick guide to the right word

If you want the cleanest, most correct phrasing:

• If you mean a church authority figure, use an ordinary.
• If you mean the jurisdiction, use an ordinariate.
• If you mean a regular, everyday person, say an ordinary person.

Why the confusion makes sense

The confusion is understandable because these words share similar sounds and roots. “Ordinary,” “ordinary authority,” and “ordinariate” cluster close together in meaning and form. It is easy for the brain to fill in a missing word that seems like it should exist.

The bottom line

“Ordinarian” is almost certainly not the best word to use in formal writing. If you came across it, check the surrounding context. You will usually find that the intended meaning points to either ordinary in a church sense, ordinariate as a structure, or simply ordinary person in everyday speech.