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Sunset over mountains illustrating "Plain as day?" blog post by the Oxford Etymologist on the OUP blog.

Plain as day?

Etymologists interacting with the public on a day-to-day basis usually receive questions about words like copacetic and shenanigans, but so many nouns, verbs, adjectives, adverbs, and even prepositions and conjunctions not crying for attention are not less, perhaps even more, interesting. Over the years, I have written about summer, winter, ice, sheep, dog, live, leave, good, bad, red, and even such inconspicuous words as but and yet, to mention just a few. We use them like old trusty tools and never stop to ask where they came from. Somebody somewhere coined them, which probably means that once upon a time they were as transparent to speakers as giggle and hiccup. But today their origin is either debatable or unknown. Isn’t a dog called a dog because it looks like a dog, runs like a dog, and barks like a dog? This is what the naïve speaker thinks, though nothing in the group d-o-g suggests a muzzle, swiftness, or any kind of explosive sound. How did day and night get their names? Aren’t the words in some way associated with light and darkness? Dictionaries know a lot about the oldest history of both but do not always provide a clue to the “motivation” that might explain their origin.

The origin of the word “day”

Let us look at day. Its past is not totally hidden (no reference to or pun on clear obscure!). Day has exact cognates everywhere in Old Germanic, including of course Old English, as well as in Sanskrit, Celtic, Slavic, and elsewhere. In Old Icelandic, the proper name Dagr has been recorded. Similar names existed in Gothic and Old High German. Does this fact testify to the word’s significance in some religious ritual? We’ll never know. What conclusion will an etymologist two thousand years from now draw about our names June, Melody, and Makepeace? Day, it should be remembered, does not always mean “a period of twenty-four hours” (as in a few days ago) or half of this period (as in day and night or daytime): it sometimes refers to “a certain period or date” as in Doomsday, the day of reckoning, I’ll remember it until my dying day, and the like. Even if you were born at night, you probably celebrate your birthday. It follows that we are not quite sure where to begin our exploration, though day as “the period of light” looks more promising: after all, law-abiding citizens tend to make their arrangements for the time when there is enough light around, while at night most of us sleep.

DAWN, the beloved sister of DAY.
(Via Pexels, public domain)

Speakers of Modern English no longer realize that dawn has the same root as day. The verb to dawn means “to begin to grow light,” and the same reference is obvious in the phrase it dawned on me. I’ll skip the phonetic part of the story (why dawn? In German, unlike what we observe in English, the connection between the noun Tag and the verb tagen is immediately obvious). Will then a search for the etymology of day take us to the idea of “light,” as suggested above? Perhaps. But first, let us remember Latin diēs “day.” Its root occurs in the English words diurnal, dial “an instrument to tell the time of day by the shadow cast by the sun,” and diary, all three of course borrowed from Romance. Though diēs and day sound somewhat alike, they are not related (a fact often mentioned in dictionaries, to warn readers against what looks like an obvious conclusion), and as though to prove the absence of ties between them, language provides us with a word like Gothic sin-tiens “daily,” in which sin– means “one” and –tien– is a cognate of the Latin word. The correspondence d (Latin) ~ t (Gothic or any other Germanic language) is regular, by the so-called First Consonant Shift: compare Latin duo versus English two.

This is what a dial looks like.
(“Ottoman Sundial at the Debbane Palace museum” by Elias Ziade, via Wikimedia Commons, CC BY-SA 4.0)

This –tien- has unquestionable correspondences all over the Indo-European world: for example, Sanskrit had dínam “day.” In Latin, we find the word nun-dinum “market held every ninth day.” Also, Russian den’ “day” (with cognates elsewhere in Slavic) and many other references elsewhere to burning, ashes, and warmth belongs here too. On the strength of, among others, several Greek words meaning “appear” and “visible,” the root of all such words has been understood as “shining.” Since the Sanskrit dèvas (obviously related) means “god,” this idea looks realistic. The Indo-Europeans habitually referred to “god” as “shining” or “sky” (such was Latin Jū-piter “sky father,” known to the ancient Scandinavians as Týr, no longer a sky god; but the name reveals his distant past). Yet it is still odd that both the words related to day and those related to diēs, though unconnected, sound somewhat alike and not only mean “day” but also begin with d. Did d suggest burning, heat, or glowing or refer to things dry and arid? Such ancient sound-symbolic associations are beyond reconstruction. They are often hard to pinpoint even in our modern languages.

Another puzzling lookalike is Sanskrit áhar “day.” It almost rhymes with Proto-Germanic dagaz but lacks d-, to which, above, I ventured to ascribe magical properties. An incredible coincidence? The Sanskrit noun has no correspondences in Germanic, Romance, Celtic, and elsewhere. (At least, none has been discovered.) Did áhar once have d- and lose it? The fertile imagination of historical linguists reconstructed several processes that could be responsible for the loss. Initial d- does sometimes disappear for no known reasons. For instance, t in tear (from the eye), which, as expected, corresponds to d outside Germanic, is sometimes absent altogether: this is true of Sanskrit and Baltic, among others. We have enough trouble with smobile (it tends to turn up wherever it wants). Did dmobile also exist? Most unlikely.

Jupiter and his degraded Scandinavian counterpart Týr.
(L: Louvre Museum. R: Icelandic National Library. Both via Wikimedia Commons, public domain.)

My point has been to show how intriguing some of our common words sometimes are. Copacetic is late (it was first recorded in the twentieth century), while day is older than most of the hills around us. But the problem of origin remains the same: people coin words and etymologists wander in a labyrinth of look-alikes, roots, fleeing initial, and final consonants, and emerge with the all-too familiar verdict: “Origin unknown (uncertain, disputed).” Yet day probably did refer to heat or a bright light. This conclusion sounds reasonable, assuming (and this a reliable assumption) that the word’s initial sense was “the time of light,” rather than “a certain period, date.” Plain as day? Almost.

Featured image by Ivana Cajina via Unsplash (public domain)

Recent Comments

  1. Constantinos Ragazas


    Though “day” may not be “as plain as day”, “night” is more clear! It likely derives from the Greek word “νυχτα” (night).

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