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Mind your plurals and singulars
Jul 03, 2014

Apparently, politicians master gobbledygook immediately upon being elected. But even gobbledygook has rules, rules that include knowing plural words from singular ones.
Recently, Justice Minister Peter MacKay, landed on the hot seat both in and out of Parliament when asked why so few women and visible minorities sit as judges in federally appointed courts.
I won’t discuss his absurd assertion that women “don’t apply” for these positions. Rather, I want to talk about his ignorance regarding plural words. He stood in Question Period and loudly declared, “There is one criteria, and one criteria only” employed by government when making such appointments.
The problem: criteria is a plural noun.
He might as well have said, “There is one circumstances,” or, “There is one reasons.” The word MacKay needed was the singular form of criteria which is criterion.
Criterion comes from the Greek kriterion (a means for judging; a standard). American Heritage provides this usage note: “Criteria is a plural form only. It cannot properly be used in any of the following ways: a criteria, one criteria, the only criteria.”
Success With Words notes: “It sometimes happens that the plural of a noun becomes an acceptable singular. This is not such a case. To use criteria as singular is a definite mistake.”
Sadly, Peter MacKay isn’t alone. The 36th president of the U.S., Lyndon B. Johnson (1908-1973), once said he would “act independently and with complete liberty with only one criteria.”
It’s very likely that one day criterion/criteria will indeed be interchangeable and acceptable as happens when a word is almost universally misused. We see this with data. But, as of now, criterion remains the correct singular.
Data, a Latin word, is the plural form of datum. It means, “Information, especially information organized for analysis or used as the basis for a decision.” Data is now used as both plural and singular. So, although we should say, “These data were incomplete,” it is acceptable today to say, “This data was incomplete.”
Media, from the Latin medium (middle), has gone the same route as data. Media, a plural noun meaning, “means of mass communication,” is usually found as a singular noun today.
American Heritage noted in 1970 that 90 per cent of its usage panel found this usage unacceptable. It’s still widely viewed as incorrect, except when used as a collective. You remember collective nouns — herd, flock, team, family, etc. In North American usage — including Canadian — a collective noun takes a singular verb.
Winner of two Pulitzer Prizes, and long-time editor of the Wall Street Journal, Vermont Royster (1914-1996), said as long ago as 1985, “The word ‘data’ is thoroughly Anglicized, and the use of Latin forms for English words is pretentious.” 
In other words, “Forget about datum.”
Regarding media, Royster observed, “I hate ‘media’ in this sense but if it must be used it is a collective noun.”
Agenda, plural of agendum, has evolved into a singular noun. Now, this plural word is pluralized as agendas while agendum has disappeared from our vocabulary.
Despite all this, criteria remains a plural.