When plurals go Latin

Nov 26, 2017

A new high school in Utah is worried about the plural form of their mascot, the phoenix.

Sure, "phoenixes" is perfectly innocuous. But parents were concerned about the other option: phoenices.

If you don't see the issue, go ahead and say that one out loud.

The school's principal said the team name would always be singular, similar to the Miami Heat or the Orlando Magic. Still, this got us wondering about other Latin plurals.

Let's start with "index."

Just like phoenix, there's no reason you can't put "es" on the end to get "indexes." In fact, that's what you'll see in most common usage. But if we're talking Latin plurals, "index" becomes "indices."

Not a fan? You're not alone. In his guide, Modern American Usage, Bryan Garner says "indices" is "high falutin and pretentious." It's not quite as pretentious as using "fora" as the plural form of "forum," Garner says, but he still doesn't like it.

Despite Garner's charming assessment, "indices" is still pretty common in scientific usage. For example, in statistics, if you're comparing a value to a standard, you'll get indices. In math, indices are a way to express large numbers. 

Here's another one -- how do you make "focus" plural? Again, adding the "es" suffix is perfectly acceptable. But most standard dictionaries include both "focuses" and the Latin plural "foci."

That presents another question -- how do you say "foci"? 

If you pronounce it with an "s" sound in the middle and a long "i" sound at the end, you're right. If you pronounce it with a "k" sound in the middle and a long "i" at the end, you're also right. Just like the two plural forms, most standard dictionaries include both pronunciations.

Are there other words that give you pause when it comes to pluralization? Let us know at rkruth@umich.edu or acurzan@umich.edu.