The Data Is/Are In: Latin Plurals Are Tricky

Rob Kyff on

Datum or data? Medium or media? Stratum or strata?

Here's a quick review of these double-dealers:

-- Datum/data: "Datum" means "a single piece of information," and its plural form is "data." But because information is usually a collection of many facts, the singular form "datum" is rarely used these days, and "data" is increasingly treated as a singular.

Like the Latin plurals "opera," "agenda" and "insignia," which long ago became singular in English (replacing their original singular forms "opus," "agendum" and "insignium"), "data" has shed its Roman toga and donned the English waistcoat of a fully Anglicized singular noun.

But beware. Some purists still cluck, cluck at the use of "data" as a singular, e.g., "the data is," "this data."

-- Medium/media: One meaning of the Latin-based singular noun "medium" is "a means of mass communication," such as radio, television or newspapers, and its plural form "media" is correctly used to refer to several forms of communication: "Our ad campaign is suitable for all these media."

But "media" is often used as a singular noun to refer to communication outlets as a collective entity, in the same way we use "the press," e.g., "The media is biased"; "The media has an agenda." While this use of "media" makes sticklers cringe, it's now accepted as standard.

Never use "media" to refer to a single medium, e.g., "Radio is a powerful media." Likewise, don't concoct the ugly pseudo-plural "medias" ("We advertised in several medias").


And save the plural "mediums" for references to T-shirts or crystal ball readers. A headline about a gang of short fortunetellers who've fled arrest, for instance, might read: "Small Mediums at Large."

-- Stratum/strata: In this case, we still retain the Latin plural. "Stratum" is the singular ("the lowest stratum of society") and "strata" (not "stratas") is the plural form ("these strata are contiguous").

The Latin plurals of many other words have largely been replaced by Anglicized plurals, e.g., stadia by stadiums, referenda by referendums, auditoria by auditoriums, fora by forums, podia by podiums. But other words have steadfastly retained their Latin plurals, e.g., criteria, phenomena, ova.

For some words, either plural form is correct, e.g., formulae/formulas; spectra/spectrums; honoraria/honorariums; millennia/millenniums.

And, as a recent celestial event reminds us, "penumbras" has not yet achieved a total eclipse of "penumbrae."


Rob Kyff, a teacher and writer in West Hartford, Connecticut, invites your language sightings. His book, "Mark My Words," is available for $9.99 on Send your reports of misuse and abuse, as well as examples of good writing, via email to or by regular mail to Rob Kyff, Creators Syndicate, 737 3rd Street, Hermosa Beach, CA 90254.

Copyright 2024 Creators Syndicate Inc.




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