The Grammarphobia Blog

What kind of abbreviation is K-9?

Q: I’m curious about the term “K-9” that appears on the doors of LAPD patrol cars that carry dogs. Is there a proper term for this type of word shortening?

A: “K-9” is obviously an abbreviation, because it’s a short form of a longer word, “canine.” But what kind of abbreviation is it?

Two common kinds of abbreviations are the “acronym” and the “initialism,” which differ in the way they’re spoken.

Since acronyms are pronounced as words and initialisms are pronounced as letters, it would appear that “K-9” could be either one. It sounds just like “canine,” and just like the individual characters “K” and 9.”

But in our opinion, it’s technically neither acronym nor initialism.”

An acronym, as we’ve written on our blog, is a word formed from elements of a longer word or phrase. But “canine” doesn’t include a “K” or a “9.”

And an initialism, as we’ve also written, is a series of letters formed from a longer word of phrase. But again, “K” and “9” aren’t part of the unabbreviated word.

We seem to be in a special category here. The “K” and the “9” merely echo sounds found in the word “canine” but don’t stand for anything resembling the longer word.

We’ve at times come across the term “pseudo-acronym,” and “K-9” might be one of those.

No dictionaries that we’ve found define “pseudo-acronym,” and there are conflicting definitions on websites. Here’s one from a paper on acronyms published by the US Department of Homeland Security:

“Pseudo-acronym: A catchall for variations and embellishments, such as creating an acronym from other acronyms (IT Acquisition Center—ITAC) or mixing abbreviations and acronyms (deoxyribonucleic acid—DNA) and ignoring words in a series just to make a pronounceable word (Princeton University Institute for the Science and Technology of Materials–PRISM), or pronouncing vowels that are not there (Guantanamo—GTMO, pronounced Gitmo) to coin a word.”

So, according to Homeland Security, you’d be on safe ground if you called “K-9” a pseudo-acronym. It’s definitely a variation or embellishment, and certainly the canines themselves won’t object.

By the way, we usually see “K-9” with a hyphen, but not always. The Los Angeles Police Department, for example, hyphenates the term on patrol cars, but usually drops the hyphen on the home page of its canine unit.

The Oxford English Dictionary doesn’t have an entry for “K-9,” but it includes the term in a citation for the noun “superintelligence.”

A Sept. 7, 1950, article in the Olean (NY) Times Herald uses the term in describing military dogs: “Super-intelligence, willingness and reliability under gunfire are requirements for the K-9 Corps.”

We found a similar use of the term in the New York Times. A Jan. 31, 1943, article describes a demonstration at the Westminster Kennel Club’s dog show “by members of the K-9 Corps—dogs now at work with the Army and Coast Guard.”

The Army’s War Dog Program, started by the Quartermaster Corps on March 13, 1942, was popularly referred to as the “K-9 Corps.”

The K-9 Corps undoubtedly helped popularize the term, though the usage was around long before the War Dog Program began.

A search of Google Books, for example, found an 1876 issue of Hallberger’s Illustrated Magazine that refers to “the various ways of rendering ‘Canine Castle,’ such as ‘K-nine Castle,’ and, better still, ‘K.9 Castle.’ ”

(Canine Castle was a kennel in London owned by Bill George, a celebrated 19th-century breeder of bulldogs.)

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