For many writers and editors, knowing these rules is a point of pride. But nowadays the rules that exist threaten to disregard, or at least confound, everyone’s “susceptibilities.” If in doubt, Bryan A. Garner advises in the entry on plurals in his Dictionary of Modern American Usage, “favor the native-English plural ending in -s.”

 

What is up today with Latin and Greek plurals, and what's a conscientious writer to do?

 

I pored over dictionaries, usage guides, and style manuals to get a snapshot of where experts stand today on the plurals of English words borrowed from Latin and Greek. The picture that emerges is blurry at best. The myriad Latin and Greek words that have entered English over the centuries are in varying stages of an often inelegant process of assimilation. Some borrowed words still follow the strict singular/plural dress codes of the old country: basis/bases, desideratum/desiderata, nucleus/nuclei, alga/algae, and stratum/strata. (As these examples make clear, one reason Latin plurals have had trouble surviving in English is that there are so darn many plural patterns. The English plural -s beckons seductively in its simplicity.) Latin also lives on in the language of the academy, in words like alumnus and alumna; however, the fact that English speakers have developed their own shortened hybrid plural, alums, may bode ill for the survival of alumni and alumnae.

 

Linguistic pluralism

Certain words maintain a kind of dual citizenship, sometimes using the original classical form and sometimes the Anglicized plural: we see atria as well as atriums, cacti as well as cactuses, and lacunae as well as lacunas. Other words still finding their plural place in English are those in which the classical plural ends in the especially unfamiliar -ata or -ices. What would you choose as the plural of apex, automaton, codex, helix, miasma, or vortex? Even Merriam-Webster’s Collegiate Dictionary, Tenth Edition, which typically favors no- nonsense modernization, waffles, listing first the Anglicized plurals apexes, automatons, and miasmas but the classical plurals codices, helices, and vortices.

 

Then there are words that came from Latin yet aren’t really foreigners any more. Such “naturalized” words include agenda and stamina. These are so well established as singular in English that few people would think to strip them down to their former Latin singular forms. Sure, agendum means “something to be done,” as Garner points out; but in English its Latin plural has also acquired a singular meaning (“a list of things to be done” or “a program”) and its own plural, agendas.

 

Other words have assimilated in a different way. Memorandum is often shortened to the very un-Latin memo, with the plural memos. In many quarters, including the Associated Press, The New York Times, and Merriam-Webster’s, its traditional plural memoranda is losing out to memorandums. Memorandum may well be on its way to joining a crowd of words ending in -um that have thoroughly forsaken their former Latin plurals, including album, asylum, delphinium, museum, nasturtium, nostrum, and premium.

 

Immigrants that can still take either -a or -ums in the plural but for which Merriam-Webster’s, at least, shows a preference for the Anglicized -ums include aquarium, equilibrium, forum, gymnasium, interregnum, mausoleum, podium, ultimatum, and vacuum.

 

New data, new media

In their refusal to follow the rules of either the new country or the old, two words from Latin—data and media—probably cause more trouble than all the others put together. So fiercely is their traditional status guarded by some editors and commentators that I’ve come to think of them as the Sacco and Vanzetti of Latin plurals, inflaming passions and provoking charges of linguistic anarchy.

 

Data “is a skunked term,” Garner writes. “Whether you write data are or data is, you’re likely to make some readers raise their eyebrows.” Once the simple plural of datum (for “something given,” like “a piece of information”), data has become much more than that. It hasn’t yet lost its plural meaning, as agenda has: it is still common in sentences like “All recent data on hurricanes are being compared.” The problem is, data also occurs frequently as an abstract mass noun taking a singular verb, singular modifiers, and the singular pronoun it. This use is especially prevalent in technology and computing: “The data is being downloaded now.”

 

Media, too, is developing in contradictory directions: often used as a singular count noun that is roughly equivalent to medium, it is also used as a collective noun, like staff or clergy, which can take either a singular or a plural verb.

 

Although most usage guides and dictionaries are content to describe the various possibilities for data and media, some style manuals still want to proscribe their use in the newer senses. Anyone who insists that data and media are nothing but the plurals of datum and medium, however, risks missing the rich odyssey traveled by each of these ancient words.

 

A hypercorrect sense of Latin plurals can lead to all kinds of problems. Beware misconstruing a few words ending in -us, such as hiatus, octopus, omnibus, and ignoramus. No Roman would make any of those plural by changing the ending to -i. The last of these words comes from the name of the protagonist, a lawyer, in George Ruggle’s play Ignoramus, written in 1615. The character’s name, Bryan Garner notes, was soon applied to all manner of know-nothings: ignoramuses. Only if we want to be thought of as one of their own kind should we call them ignorami.

 

Here's my best advice: If you are writing for publication, check that publication's style manual or do a quick search to see how plurals are treated in its pages. If that's not helpful, trust your ear and write so that the words with Latin and Greek heritage don't change your tone. Of course, you can always flag a plural for your editors, but many will probably shrug. (They haven't read an article as long-winded as this one, I'm betting!)

 

—Constance Hale