Plurals of Non-English Words in an English-Language Context

The Chicago Manual of Style recommends that in an English-language context, “plurals of non-English words should be formed as in the original language” (11.3). So if you were to use, say, the Italian word for “flowers” (fiori) in an English sentence, it could look like this: “I picked some lovely fiori in Tuscany.” The singular form of fiori is fiore, and according to Chicago’s principle the plural is formed as in Italian, fiori, and not by adding the letter s to the end, fiores, as you would form a plural in English. For languages that typically do not distinguish between singular and plural forms, such as Japanese, the plural is formed the same way as the singular. For example, the Japanese word for cat or cats is 猫 (neko): “I saw two orange neko in the alley today.” (See our previous post on italicizing non-English terms in an English text.)

To form the possessive of this kind of term, you can add an apostrophe and an s (in roman font) to the end of the word, as you would form a possessive in English: “the fiori’s smell.” Or you could rephrase to avoid having to use an apostrophe and an s: “the smell of the fiori.”

These principles are relatively straightforward. But sometimes it can be unclear which plural form to use if a term has been naturalized into English—that is, if a non-English term is in such frequent use in English that it is considered an English term. When terms are naturalized into English, their plurals are usually formed according to Chicago’s principle, hence “raisons d’être” and not “raison d’êtres,” “cognoscenti” and not “cognoscentes.” But take the example of the term persona. Originally a Latin word, it has long been accepted as an English one as well. The Latin plural is personae, which is often how it is formed in English, but perhaps just as often one sees personas instead, and indeed both are acceptable. The plurals of this kind of term often vary, and it behooves the careful writer to give them some thought.

Consider ignoramus. Not wanting to be thought one yourself, you might look into how to make the word plural when the need for describing those unfortunate individuals arises. The word ignoramus comes from the Latin verb ignorare, but in the first-person plural form, which might be translated as “we don’t know.” It is not, in fact, a singular noun. If it were a singular noun, then the plural form would be ignorami, which is how one often sees it written in English. From a strictly grammatical standpoint, though, this is incorrect. There’s no way to make the Latin word plural, because it’s not actually a noun! So in this case the English ignoramuses is perhaps the best way to make the word plural.

Other tricky examples of naturalized terms abound. Both curricula and curriculums are acceptable, and the same goes for syllabi and syllabuses. However, prolegomena seems to be the only accepted plural form of prolegomenon, not prolegomenons. The dictionary gives both phalanxes and phalanges as the plural of the Greek word phalanx, usually used to describe a military formation. But in English the plural phalanges (which is how the Greek plural would be written) is the medical term for fingers or toes, whereas the plural phalanxes means the military units. In Latin the plural of the word apparatus is also apparatus. In English the plural apparatuses is perhaps the most common form, but the plural apparatus is also accepted.

While the dictionary is usually your best guide for spelling non-English terms, sometimes a little extra research is helpful to make sure you’ve chosen the correct plural form in your writing.

Work Cited

The Chicago Manual of Style. 18th ed., U of Chicago P, 2024, www.chicagomanualofstyle.org/home.html.