Why is the letter Z, specifically, associated with sleeping? It seems silly to have a letter correspond with sleep at all, but even sillier that we don't do this with any other action. You don't hear being awake referred to as "catching some A's."
— Ethan Reber
Sorry to go off on a tangent, Ethan, but you know what they call sleeping in the U.K.? Catching some zeds. I get this from my assistant Fierra, who delightfully proclaims her Britishness every time she opens her mouth.
Z isn't associated with sleeping, specifically, but rather with snoring. You may be one of the fortunate few having no personal acquaintance with this phenomenon. I don't have much familiarity with it, either, but mostly because I'm asleep when I do it. Ms. Adams tells me Z doesn't adequately convey the experience, which she says is like hearing a drowning man being eaten by a squid. Considering that a realistic representation would be something like gasp-choke-grunt-chew-smack, I think we can agree a simple Z is good enough.
Z as shorthand for snoring is a relatively recent invention. It came into common use with the advent of comics.
Figuring this out this took a while. The Oxford English Dictionary wasn't much help. It credits the first use of Z to signify buzzing to Henry Thoreau, who in 1852 wrote, "The dry z-ing of the locust is heard." However, the first use of "z-z-z" to represent snoring given in the OED is from a 1924 publication by the American Dialect Society, implying it was in popular use some time before.
Once again my assistant Una stepped into the breach. Searching for the letter Z in the world's databases turned up a considerable number of false positives, but by and by she found an instance of Z = snoring in the humor section of the January 1919 Boy's Life, the Boy Scout magazine. Pushing on, she found the Krazy Kat comic strip of May 28, 1916, in which a sleeping bear emitting Z's is awakened when Ignatz the mouse playfully chucks a rock at its head.
It soon became clear comics were the principal Z vector. In the Katzenjammer Kids strip of February 16, 1913, the sleeping Captain is generating b-z-z-z's and z-z-z's prior to having his rocking chair pulled over backward by the disrespectful Kids opening the door.
In the November 17, 1907, edition of the comic strip The Fineheimer Twins, a blatant Katzenjammer knockoff, Una found a peg-legged man producing a whole alphabet of sounds while sleeping, including "g-r-r-k-k-k-k," "z-z-z-c-r-r-k-k-k-k," and plain old "z-z-z," until a fishbowl is upended on his head.
But the ur-instance of Z, or at least the earliest that's come to light, was turned up by Sam Clemens of the Straight Dope Science Advisory Board. It was again from the Katzenjammer Kids, and again featured the snoring Captain, this time suspended in a hammock, unaware he's inventing an enduring comic strip trope. The unimpressed Kids trim his beard with a push mower, then end further Z-ifying by cutting the hammock's ropes. Date of these epochal events: August 2, 1903.
Wanting to be certain there'd been no prior usage, and more important hoping to outdo Sam, Una spent several weekends searching through thousands of turn-of-the-century comics, many available only on microfilm of old newspapers. Immersing herself in far more 1890s pop ephemera than was probably safe, and getting briefly distracted by the implied lesbianism of the 1905 strip Lucy and Sophie Say Good Bye, she discovered other representations of snoring such as "ur-r-r-awk," musical notes, and stars. But she was obliged to conclude that Katzenjammer Kids creator Rudolph Dirks, who drew the comic until 1912, was the first to depict snoring with Z's.
Were Rudy still around we might X, Y, Z? Surely he'd say: It was simple and it didn't crowd the panel.
Still, where did Z come from? Given Dirks's German birth and the heavy German accents of the Katzenjammer characters, one might think it was of German origin. However, Una was unable to find any German uses before 1903.
That raised the question of how snoring is represented in other cultures. Una discovered the following:
• Germans use "chrrr," which considering the typical German pronunciations of ch and r — i.e., you sound like you're getting ready to use the spittoon — is a lot closer to snoring than "zzz."
• The French, who also favor a sonically rich r, use "rrroooo," "rrr," "roon," "ron," and so on. The Spanish likewise use "rooooon."
• The Japanese use characters that transliterate as "guu guu," while speakers of Mandarin Chinese use characters sounding like "hu lu."
• Finns use "kroohpyyh," which I'm guessing gives a hint of what I sound like.
Too much to remember? Macht's nichts. Z, like so many other effusions of American pop culture, is in common use worldwide.
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