- n. The cardinal number occurring after seven and before nine.
You may or may not know that the system of numerals (from the Middle French numéral ← Latin numerālis ← numerālis (“number” or “quantity”) ← PIE *nem (“assign, distribute, allot”)) we use is the sole province of very smart people in the near East. Though our language and literary culture is dominated by the Greeks and Romans and later by western Europe, the early days of math owes just about everything to such tongue-twistable personages as Aryabhata (positional notation), Al-Khwarizmi (algebra), and Brahmagupta (zero). What’s more, our numerals are relatively straightforward transplants from the Hindu-Arabic system of numerals. Such was the influence of the East on early math and numerical theory that there was never any real competitors in Europe—the unwieldy Roman Numeral system simply couldn’t compete, lacking any real form of positional notation or zero, and being almost impossible to work with in algebra.
The general trend in the history of English is for areas of law and learning to be Latinate (either directly from Latin in the case of judicial matters or via French in most everything else) while everyday things like swearing came from the lower-class Ango-Saxon. One would expect that, since numbers and math constitute a rather high-brow pursuit, our words for numbers should be Latinate as well. In an unexpected twist of history, this is not so, although many of our numeral names have a common ancestor for both the Latin and the Anglo-Saxon forms.
A note on vocabulary. When we talk about numbers, they can take a variety of grammatical forms. The numeral itself, e.g. “one” or 1, is known as a “cardinal” number. When using the number to describe a position in a sequence, e.g. “first” or 1st, it is an “ordinal” number (think ordinal→order). The term “multiplier” refers to the form of the number used when (wait for it) multiplying, e.g. single or double. A form which only exists for the first three numbers is the adverbial, as in “once”.
“One” is one of those numbers that makes no sense to children, since it seem counterintuitive in its pronunciation: by analogy with ones like “done” it should be pronounced simply “uhn”, or perhaps “own”. In fact, it used to be pronounced as the latter, until the 14th century, when it underwent a spontaneous mutation in western England. A popular Biblical translation, the Tyndale Bible, spells it won. It comes to us from the Old English ān, the Proto-Germanic *ainaz, and the PIE *oinos, all with the same meaning of singularity. You can see the root at work in the modern German ein as well as the Latin unus, from whence “unity” and “universal”.
On a completely different etymological track, the ordinal form of one, “first”, comes from the Old English fyrst, the Proto-Germanic *furisto, and ultimately from the PIE root *pro-1.
The adverbial form of one is the straight-forward “once”, from a grammatical declension of the Old English. The multiplier, single, is yet another separate etymology. It comes from the Old French sengle, the Latin singulus, a derivation of simplus, which has the same meaning and forms the root of our “simple”.
Another word that doesn’t quite look like it sounds is “two”, which comes from the Old English twa, a form of twegen from whence our rather archaic twain (e.g. “cleft in twain”). It’s from the Proto-Germanic *twai and ultimately the PIE *duwo, all with the same meaning (number meanings tend to stay constant over time). The migration from the original dʰ or d is another example of Grimm’s Law (see footnote), which is why Germanic languages ended up with the dental t and non-Germanic languages like Latin retained d words like duo and gave us dual. The reason why modern German has zwei instead of two is due to a second Germanic consonant shift known as the High German consonant shift; modern German descended from OHG, but other Germanic branches such as Dutch (twee) or Swedish (två) did not.
Two’s adverbial form is twice, the etymology of which is as straightfoward as it suggests. Its multiplier, double, comes from the Old French doble, from the Latin duplus, all the way back to the aforementioned duo. Duplus, by the way, still gives us duplicity and duplex, among other words.
The ordinal form of two is “second”, from the identical Old French, and finally from the Latin secundus, which means “to follow in order”. The same root which underlies this also gives us sequel and sequence
As Schoolhouse Rock once crooned, “Three is a magic number”. It’s the last in a well-known grouping (sort of like the modern day “A, B & C”, which is why it’s the last number to have an adverbial form (“thrice”), though even this has become archaic.
Three comes to us from the Old English þreo, from the Proto-Germanic *thrijiz, and the PIE *trejes. Once again, Grimm’s Law is at work: the original dental t of PIE gave way to a th (or θ/þ2). Hence, we have three; due to the aforementioned High German consonant shift, the th morphed into an initial d, hence the German drei. This was the last phase of the High German shift, occurring in the 9th and 10th centuries, and the only part of it to work its way into Dutch as well, hence the Dutch drie.
Three’s ordinal form, third, comes again from the Old English, this time from a metathesis (rearrangement of sounds within words) of þridda; in fact, it was not uncommon to hear thrid well unto the 16th century. Ultimately, it comes from the PIE root *tritjos, which gives us tertiary (cousins of primary and secondary) from Latin.
The multiplier of three, triple, is from the Latin triplus, a combination of the tri- prefix and -plus, which means “fold”—literally “threefold”, a construction still used today. Note the discrepancy between triple and double; the absorption of these multiplier words into French often changed the internal p into a b, and so these words were effectively absorbed twice. One can still find “duple” used (especially in musical vocabulary, which was heavily influenced by the Italian, which kept the internal p), just as one can also find treble used both in music (oddly enough) and as a synonym for triple.
Four marks a change in our sequence of numbers; we’ve passed the more common one, two, and three and our etymologies get proportionally more complicated. The lineage itself is easy: the Old English feower comes from the Proto-Germanic *petwor- and the PIE *kwetwer-. This earliest root explains the Latin quattuor (and hence quaternary and the modern multiplier quadruple; beyond that, as Douglas Harper notes, the evolution of the Germanic is as-yet unexplained. The usual function of Grimm’s law would turn the *kʷ of the PIE root into a hw sound, which it doesn’t. The change from the Proto-Germanic p to the later Old English f, however, does appear to follow the established pattern. Modern German and Dutch vier appear to buck the trend until one realizes that the letter V (as opposed to the phoneme V is often pronounced as F in Germany words such as vier or Volk (“folk”).
In the case of four, its ordinal form is a relatively simple affair, attaching the -th suffix to the base word. This particular suffix, which applies to all numbers except the first three, is derived from the Old English -þa, itself a derivation of an Indo-European superlative suffix—that is, serving a function similar to Modern English’s -est. The multiplier maintains a similar pattern, pairing the Latin root qua[t/d] with the -uple suffix, which is from the aforementioned -plus (“fold”) suffix.
Five is an adaptation of the Old English fif and Proto-Germanic *fimfe, ultimately derived from the PIE *penkʷe. You can still see the PIE influence in non-Germanic branches such as the Greek pente, from whence comes our well-known prefix of penta-—e.g. pentagram, Pentecost, Pentateuch. How the Latin quinque was managed from *penkʷe is a little strange and not extensively documented. It appears, however, that in circumstances when the PIE has a *p and a following kʷ, the initial p was often assimilated, so that *penkʷe became, effectively, *kʷenkʷe… or quinque.
The ordinal “fifth” is from the Middle English fift, which was altered by analogy with the aforementioned fourth, beginning the trend that will mark the rest of the ordinals we’ll cover.
Six invariably makes schoolchildren giggle, since its Latinate root is sex. It gets that root from the PIE *seks, which gave rise simultaneous to the Latin as well as the Proto-Germanic *sekhs and eventually the Old English siex. The Latin gave rise to the name of the sextant, an early navigational device. In case you’re wondering, sex in the sense of coitus or gender is from a different Latin source (sexus, related to secare, “to cut”).
The ordinal sixth comes from the Old English syxte and eventually altered by analogy with the now-established pattern.
Our other well-known prefix for six, hex- (e.g. a hex-head bolt), is from the Greek ἕξ, which is Epilson and Xi, but the diacritical mark above the Epilson indicated a rough aspiration, or “H” sound.
Seven is the only base numeral that is not monosyllabic. It comes from the Old English seofon, the Proto-Germanic *sebun, an the PIE *septm. In the Latinate branch, we get septem, from whence septuple (e.g. septuplets). On the Germanic side, it follows a similar evolution to our modern “heaven”, which was heofon in Old English.
Despite the similar appearance, the Latin septem is not related to the septum (the wall between the nostrils) which is from the Latin word for “fence”; nor is it related to a septic system, which is a Latin derivative of an earlier Greek word meaning “to rot”. On the subject of Greek, that language’s word for seven, hept- is once again a substitute of an initial s- for an h. You can see this same phenomenon on other words like semi/hemi (“half”), but I can’t for the life of me find any reason for it, other than a suggestion that the prehistoric Greek maintained the S.
Eight demonstrates a number of interesting etymological phenomenon all at once, which is why I chose it as the star word for this entry. Originally eighte, it comes from ehte, from Old English æhta, from the Proto-Germanic *akhto(u) and finally the PIE *okto. One can easily see where the Latin root octo- came from, evident in our octopus, octothorpe, and, less appealingly, “Octo-mom” and her octuplets. Ernest Klein3 thinks it is a “dual form”, that is, meaning “twice four”.
How it came to be spelled “eight” as opposed to the somewhat more reasonable ehte has to do, according to Doug Harper, with a “scribal habit” of the Middle English period. It was common in Chaucer’s day to pronounce the consonants in words like fight, eight, and [k]night, so that “knight” became k’nikt4. Sometimes, the gh group would be substitute by the yogh (ȝ), which represented the phoneme /x/ in this instance, though it was a workhorse symbol that served a lot of purposes for a lot of languages.
The Normans, Latinate as they were by way of French, began a program to replace all non-Latin letters with digraphs (two or more letters which replace a single one). Thus, niȝt became night and eȝt became eight, and as the spelling changed, so did the pronunciation, until finally these internal gh clusters became silent altogether.
Nine comes from the Old English nigen, from the Proto-Germanic *niwun, from the PIE (e)newn. The neat and tidy etymology of this one gives us the Latin novem (yes, from whence November), the Greek ennea, the German neun, and the Danish ni. Similarities to the German word for “no”, nein, are coincidental, since the latter comes from the PIE *ne-.
Zero was a latecomer to the numeral game, as I mentioned long ago in the introduction. Though it makes perfect sense to modern readers, it is not quite the fundamental concept that, e.g. “one” is. Its etymology is just as nontraditional: from the Italian zero, it came from the Medieval Latin zephirum, itself from the Arabic صفر (sifr, our “cipher”), which is a rather poetic translation of the Sanskrit sunya-m, which means “empty place” or “desert”. In this way, it’s actually the neatest of the numerals etymologically, even if it’s something of a stepchild.
- The mutation of the initial p sound to f is a well-documented phenomenon known, along with other similar shifts, as Grimm’s Law. Non-Germanic PIE-derived languages like Latin maintained the initial plosive p, hence pro- words like “prologue“[↩]
- The letter þ is called “thorn” and was originally a runic symbol, pronounced as a dental fricative and represented in modern phonetic spellings as the Greek symbol theta (θ) [↩]
- Klein’s Comprehensive Etymological Dictionary of the English Language, 1971[↩]
- And making the opening joke about “filthy English k’niggits” from Holy Grail a little more accurate[↩]