Why Does ‘Zzz’ Mean Sleep?

In the 1890s, a distinctly American art form emerged: the comic strip. But artists quickly ran into a particular difficulty. Some comic characters’ hijinks required a sleeping victim for full comedic potential.

But how could an artist convince the audience that a character was asleep and blissfully unaware instead of merely lying down? Visually—and, importantly for comics, dynamically—portraying a state in which most people are usually silent and still isn’t easy. So, in the end, the answer was to highlight the noisy part of it: snoring.

The Origins of Zzz
Do Other Languages Use Zzz to Represent Sleep?

The Origins of Zzz

Comic artists tried a variety of representations for snoring before there was an accepted convention. Often, it was some combination of imitative letters, including zzggrrhh, ur-r-r-awk, or z-z-c-r-r-k-k-k-k. But symbols were also used, like stars and musical notes. Some artists even drew a log getting sawed above the person’s head in reference to the popular idiom for sleeping. The less imaginative sometimes simply wrote, “snore.”

One representation ultimately stuck, though: the letters Zzz. Its first use can be traced back to 1903 in the comic Katzenjammer Kids, created by Rudolph Dirks. In it, the snoring Captain sleeps peacefully in his hammock, emitting z’s, while the mischievous Katzenjammer kids cut his beard with a mower and then cut the hammock’s strings.

Dirks didn’t use Zzz exclusively in his portrayals of snoring, but he often relied on variations of it. Other comics, such as The Fineheimer Twins, Krazy Kat, and the humor section of Boy’s Life, the Boy Scout Magazine, all followed suit by using z’s throughout the 1910s. By 1918, we know its place was solidified in the lexicon, having earned its own entry in the American Dialect Society’s notes: “z-z-z (sound of whispering or snoring).”

Do Other Languages Use Zzz to Represent Sleep?

Despite the letter Z being more of a visual representation of sleep than a verbal one, it has influenced language across the globe.

In the 1940s, the verb zonk (out) emerged to convey suddenly falling into a deep sleep. The phrase catch some Zs is also one of the most obvious results of Zzz’s popularization, though it’s pronounced a little differently in many English-speaking countries around the world, like the UK, Canada, and Australia. There, a tired person needs to catch some “zeds,” and a nap has even come to be called a “zizz.”

Many languages have their own unique noises or representations for snoring aside from Zzz as well. Germans, for example, use chrr, and French and Spanish speakers also lean into their r sounds with variations of a sound like roon or just plain rrr. The Japanese, meanwhile, use characters that sound like guu-guu, and in Mandarin it’s akin to hu-lu. But even though the regional onomatopoeia may vary, Zzz has made its mark; it’s recognized internationally as a symbol for sleep.

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