This is the 250th anniversary of the United States, and as a result we’ve heard the term “semiquincentennial” a lot. (Well, a lot more than usual.) That reminded me of several past questions about such terms, so we’ll take a look at them now, starting (after a quick introduction) with one asked 25 years ago about the 225th anniversary.
Greek and Latin number prefixes
Before we get to the main issue, it will be helpful to look at how numbers are handled in general. Here is a question from 2001:
Prefixes in Math What are the prefixes for 7, 8, 9, and 10?
I answered:
Which prefixes are you referring to? There are actually at least two sets of number prefixes in English, derived from Latin and Greek. The Latin are used (a little modified) in names for large numbers: Large Numbers and Infinity - Dr. Math FAQ http://mathforum.org/dr.math/faq/faq.large.numbers.html Decillion, Vigintillion, Trigintillion... - Dr. Math Archives http://mathforum.org/dr.math/problems/trichardt12.10.98.html The Greek forms are used in names of polygons: Naming Polygons and Polyhedra - Dr. Math FAQ http://mathforum.org/dr.math/faq/faq.polygon.names.html Here is a list of them: Number Greek Latin ------ ----- ----- 1 mono- uni- 2 duo-/di- duo-/bi- 3 tri- tri- 4 tetra- quad- 5 penta- quint- 6 hex- sex- 7 hept- sept- 8 oct- oct- 9 ennea- non- 10 dec- dec- 20 icosa- vigint- 30 triaconta- trigint- 40 tetraconta- quadragint- 50 pentaconta- quinquagint- 60 hexaconta- sexagint- 70 heptaconta- septuagint- 80 octaconta- octogint- 90 enneaconta- nonagint- 100 hect - cent- I haven't found all of these in dictionaries; the higher ones are taken straight from Latin or Greek rather than from standard English prefixes, and many have several variants. (You can find the teens in the pages I cited.) You may enjoy looking them all up in a dictionary to see what words use them.
We’ll be seeing the Latin prefixes a lot here; notice that “-gint-” means “tens”, following the number of tens.
Names for anniversaries: centennial, etc.
Here is that first 2001 question:
Word for a 225th Birthday This year America is celebrating its 225th birthday. As we celebrated the bicentennial in 1976, is there a term for 225 years? Thanks, Jerry
I answered, well remembering the bicentennial year, 1976, when I grew my now 50-year-old beard; I did a little research:
Hi, Jerry. There are words for such odd anniversaries, but I'm not sure they are at all standard. I first found this site Gustavus (College) Usage: An Alphabetical Listing http://www.gustavus.edu/oncampus/publications/style/alpha.cfm which, under anniversaries (institutional), gives a list: Colleges and universities are big on anniversary celebrations, so it's important that we're proper in our references to them. Most of the following terms are tremendously awkward, so alternative labels like "jubilee" may be preferred. 50 = quinquagenary (golden) 75 = terquasquigenary (diamond) 100 = centennial 125 = quasquicentennial 150 = sesquicentennial 175 = terquasquicentennial 200 = bicentennial 225 = bicenquasquigenary 250 = bicenquinquagenary 275 = bicenterquasquigenary 300 = tricentennial
(I’m going to put words that turn out not to be valid in red.)
These are based on reasonable Latin words, but mix together forms with “-ennial” (“years”), and forms with just “-ary” (which comes from Latin “-arius”, as in “denarius”, meaning “consisting of ten” because it was worth ten “asses”). The “-gen” for “tens” (corresponding to “-gint” that we saw above) would make “gen-ennial” sound odd.
In the really complicated words, “sesqui” means “half more”, or “1.5 times”, so that “sesqui-centennial” means 1 1/2 hundred; and “quasqui” means “a quarter more”, or “1.25 times”, so that “quasqui-centennial” means 1 1/4 hundred.
They appear to be taking “bi-cen-quasqui-genary” to mean “two-hundred-and-a-quarter-of-a-hundred”. But, if anything, I’d take it to mean “two hundred and 1.25 tens”, or 212.5, not 225. I suspect they intended something like “bi-cen-quasqui-centenary”, but even that, as we’ll see, is questionable.
Similarly, three times they take “terquasqui-” to mean “and 3/4”, which I understand to be a recent coinage, but not unreasonable. But then, for example, “terquasqui-genary” would mean 1 3/4 of 10 (17.5), not 3/4 of 100. Their “terquasqui-centennial” is correct, and “bi-cen-terquasqui-genary” has the right pieces, not quite assembled correctly as I see it, but I’ve seen nothing better.
They take “bi-cen-quinqua-genary” to mean “two-hundred-and-five-tens”, which makes sense.
Some of these have several forms; for 300, we can use “tricentennial” or “tercentennial” with the root for “yearly”, or “tricentenary” or “tercentenary” without it; I graduated from high school in our town’s “tercentenary” year, on the stage to be used for that celebration, which makes it very memorable.
I searched the Web, and found that some of the above appear only at that site, so I don't really trust it. Also, I know the 300th anniversary as the "tercentenary"; I think that's the preferred name, though both are in my dictionary. I find "quasquicentennial" in use elsewhere, but not "bicenquasquigenary," which is the one you are asking about. So I kept looking. Here's a list I think I trust more: MIStupid.com - The Online Knowledge Magazine - Anniversaries http://mistupid.com/months/annivnames.htm Year Anniversary Name 2nd Biennial 3rd Triennial 4th Quadrennial 5th Quinquennial 6th Hexennial 7th Septennial 8th Octennial 9th Novennial 10th Decennial 11th Hendecennial 12th Duodecennial 13th Tredecennial 15th Quindecennial 16th Sextodecennial 17th Septendecennial 20th Vigintennial 30th Trigentennial 40th Quadragennial 50th Quinquagenary or Jubilee 60th Sexagennial 70th Septuagennial 75th Septuagesiquintennial 80th Octogintennial 90th Nonagintennial 100th Centennial 125th Quasquicentennial 150th Sesquicentennial 175th Septaquintaquinquecentennial 200th Bicentennial 225th Quasquibicentennial 250th Semiquincentennial 300th Tercentennial 350th Semiseptcentennial 400th Quatercentenary 500th Quincentennial 600th Sexcentennial 700th Septcentennial 800th Octocentennial 1,000th Millenial 15,000th Quindecimillenial That makes this the "Quasquibicentennial" (which means, "a quarter more than 200 years").
This list is fairly consistent, using “-ennial” for “years” (mostly), but some still feel a little off to me. Their word for 225, “quasqui-bi-centennial”, can be understood to mean “2 1/4 hundred”; but I would understand it as 1.25 times 200, which is 250. Similarly, one might call the 250th the “sesquibicentennial” (“1/2 more than two centuries”), but properly that would mean “1 1/2 times 200”, which is 300. Instead, they properly take 250 as “half of 500”, which is exactly the official U.S. name for the 250th.
So where “sesqui-” is sometimes taken as “1/2 more than”, its proper meaning is “half again as much as”, or “1 1.2 times”; in Latin “2 1/2” is not “bisesqui” or “sesquibi”, but “sester-“, which means “1/2 less than 3” (or “halfway to 3”), as in a coin called a “sestertius” or “sesterce”, worth 2 1/2 asses (1/4 of a denarius, which was 10 asses). (The unit of money was an “as”; no donkeys were hurt in making these coins.) We’ll see that soon.
A few of the words in this list accidentally use Greek prefixes. And they misspelled “millennial”.
So I kept looking. What if someone actually gave sources?
Here is an alternative discussion I found: Naming the Anniversaries - Glenn Kersten (Reference service, Suburban Library System, Burr Ridge, Illinois) http://www.sls.lib.il.us/reference/por/features/97/annivers.html This looks the most "official" but it doesn't include 225. For the sake of repetitiveness - I mean, completeness - here's their list: The March 1988 issue of Quidnunc, erstwhile newsletter for Illinois system and R&R reference librarians, included a comprehensive though not all-inclusive list of anniversary names, many of which were verified in the Oxford English Dictionary. Below is a new list based largely on the Quidnunc list, with a few more recent additions. The abbreviations in the Authority column refer to the Random House Dictionary (RHD) and the Oxford English Dictionary (OED). Those without dictionary authority are listed as "Proposed." (The latter were created using Latin number forms, but cannot be considered to be official terms; they were created by individuals without consensus.) Number of Years Anniversary Name Authority --------------- ---------------- --------- 2 Biennial OED 3 Triennial OED 4 Quadrennial OED 5 Quinquennial OED 6 Hexennial Proposed 7 Septennial OED 8 Octennial OED 9 Novennial OED 10 Decennial OED 11 Hendecennial Proposed 12 Duodecennial OED 13 Tredecennial Proposed 15 Quindecennial OED 16 Sextodecennial Proposed 17 Septendecennial OED 20 Vigintennial Proposed 30 Trigentennial Proposed 40 Quadragennial OED 50 Quinquagenary or Jubilee OED 60 Sexagennial Proposed 70 Septuagennial Proposed 75 Septuagesiquintennial Proposed 80 Octogintennial Proposed 90 Nonagintennial Proposed 100 Centennial OED 125 Quasquicentennial RHD 150 Sesquicentennial OED 175 Terquasquicentennial or Septaquintaquinquecentennial Proposed 200 Bicentennial OED 250 Semiquincentennial Proposed 300 Tercentennial OED 350 Semiseptcentennial Proposed 400 Quatercentenary OED 500 Quincentennial OED 600 Sexcentennial Proposed 700 Septcentennial Proposed 800 Octocentennial OED 1,000 Millenial OED 15,000 Quindecimillenial OED It looks as if you can use any word you like for the 225th, at your own risk.
This includes that currently official word for 250, and the one that I would most question is the alternative for 175, “Septa-quinta-quinque-cent-ennial”, which would mean “7-5-5-hundred”, if anything. (Wikipedia explains it as coined by a lexicographer, and agrees it is nonsense.)
They again misspell “millennial”. That’s not uncommon, but is definitely wrong.
The ultimate list
Today, of course, we’d just check Wikipedia; here I’ll ignore minor variations, and I’ll add my own notes on the literal meaning of each word:
| Anniversary | Latin-derived term | Meaning |
| 6 months | Semiannual | Half-year |
| 1 year | Annual | Yearly |
| 2 years | Biennial | Two-yearly |
| 3 years | Triennial | Three-yearly |
| 4 years | Quadrennial | Four-yearly |
| 5 years | Quinquennial | Five-yearly |
| 6 years | Sexennial | Six-yearly |
| 7 years | Septennial | Seven-yearly |
| 8 years | Octennial | Eight-yearly |
| 9 years | Novennial | Nine-yearly |
| 10 years | Decennial | Ten-yearly |
| 11 years | Undecennial | One-[and]-ten-yearly |
| 12 years | Duodecennial | Two-[and]-ten-yearly |
| 13 years | Tredecennial | Three-[and]-ten-yearly |
| 14 years | Quattuordecennial | Four-[and]-ten-yearly |
| 15 years | Quindecennial | Five-[and]-ten-yearly |
| 16 years | Sexdecennial | Six-[and]-ten-yearly |
| 17 years | Septendecennial | Seven-[and]-ten-yearly |
| 18 years | Octodecennial | Eight-[and]-ten-yearly |
| 19 years | Novemdecennial | Nine-[and]-ten-yearly |
| 20 years | Vigintennial | Twenty-yearly |
| 25 years | Quadranscentennial | Quarter-hundred-yearly |
| Quinvigintennial | Five-[and]-twenty-yearly | |
| 30 years | Trigintennial | Thirty-yearly |
| 35 years | Quintricennial | Five-[and]-thirty-yearly? |
| 40 years | Quadragennial | Forty-yearly |
| 45 years | Quinquadragennial | Five-[and]-forty-yearly |
| 50 years | Semicentennial | Half-hundred-yearly |
| (not quinquagennial??) | Fifty-yearly | |
| 55 years | Quinquinquagennial | Five-[and]-fifty-yearly |
| 60 years | Sexagennial | Sixty-yearly |
| 65 years | Quinsexagennial | Five-[and]-sixty-yearly |
| 70 years | Septuagennial | Seventy-yearly |
| 75 years | Semisesquicentennial | Half-one-and-a-half-hundred-yearly |
| 80 years | Octogintennial | Eighty-yearly |
| 90 years | Nonagintennial | Ninety-yearly |
| 100 years | Centennial | Hundred-yearly |
| 125 years | Quasquicentennial | One-and-a-quarter-hundred-yearly |
| 150 years | Sesquicentennial | One-and-a-half-hundred-yearly |
| 175 years | Dodransbicentennial | Quarter-less-than-two-hundred-yearly |
| Demisemiseptcentennial | Half-half-seven-hundred-yearly | |
| Quartoseptcentennial | Quarter-seven-hundred-yearly | |
| Terquasquicentennial | Three-quarter-more-than-hundred-yearly | |
| 200 years | Bicentennial | Two-hundred-yearly |
| 225 years | Quasquibicentennial | Quarter-more-than-two-hundred-yearly? |
| 250 years | Sestercentennial | Half-less-than-three-hundred-yearly |
| Semiquincentennial | Half-five-hundred-yearly | |
| Bisesquicentennial | Two-and-a-half-hundred-yearly? | |
| 275 years | Bicenterquasquigenary | Two-hundred-[and]-three-quarter-more? |
| 300 years | Tercentennial | Three-hundred-yearly |
| 350 years | Sesquarcentennial | Half-less-than-four-hundred-yearly |
| Semiseptcentennial | Half-seven-hundred-yearly | |
| 375 years | Terquasquicentennial | Three-[times]-quarter-more-than-hundred-yearly? [Same word used for 175!] |
| 400 years | Quadricentennial | Four-hundred-yearly |
| 450 years | Sesquincentennial | Half-less-than-five-hundred-yearly |
| 500 years | Quincentennial | Five-hundred-yearly |
| 600 years | Sexacentennial | Six-hundred-yearly |
| 700 years | Septuacentennial | Seven-hundred-yearly |
| 800 years | Octocentennial | Eight-hundred-yearly |
| 900 years | Nonacentennial | Nine-hundred-yearly |
| 1000 years | Millennial | Thousand-yearly |
| 1500 years | Sesquimillennial | Half-more-than-thousand-yearly |
| 2000 years | Bimillennial | Two-thousand-yearly |
| 3000 years | Trimillennial | Three-thousand-yearly |
| 4000 years | Quadrimillennial | Four-thousand-yearly |
| 5000 years | Quinmillennial | Five-thousand-yearly |
| 6000 years | Sexmillennial | Six-thousand-yearly |
| 7000 years | Septmillennial | Seven-thousand-yearly |
| 8000 years | Octomillennial | Eight-thousand-yearly |
| 9000 years | Novamillennial | Nine-thousand-yearly |
| 10,000 years | Decamillennial | Ten-thousand-yearly |
| 100,000 years | Centamillennial | Hundred-thousand-yearly |
As noted by (?), I don’t like several of these, for which no explanation is given there. Note that
- “semi-” means “half”,
- “sesqui-” means “one and a half”,
- “quasqui-” means “one and a quarter”,
- “ses-” means “a half less than”,
- “dodrans-” means “a quarter less than”.
The last two evidently are not multiplicative, though most sources I find say that the former two are.
Don’t confuse “sesquicentennial” with “sesquincentennial”!
They still use quasquibicentennial, so I guess I have to reluctantly accept it for 225. It appears that “quasqui-” is an invented prefix, not directly based on Latin, so perhaps we are free to define it not consistently as 1.25, but as “-and a quarter” here, mostly because there’s no better choice.
But for 250? For ease of pronunciation, I’d choose sestercentennial. Except that no one unfamiliar with ancient Roman coins would know what it means!
Now let’s look at a few related sets of words.
Names for age ranges: septuagenarians, etc.
The next month we got this question:
Age Classifications Hello Dr. Math, I'm trying to complete a table for age classes. So far, I have found: quinquagenarian = 50s sexagenarian = 60s septuagenarian = 70s octogenarian = 80s nonagenarian = 90s I could guess that someone in his or her forties is a tetragenarian, but do you have a more definitive answer for the gaps in my list? I'm also looking for 100s, or someone over 100 years of age, and if there is a definition for 110s? Are these Greek- or Latin-based? Best Regards, Scott Ingwersen
I answered again:
Hi, Scott. The "s" in "sexa" and "septua" tells us they are Latin (the Greek prefixes are "hexa" and "hepta"). (See our Dr. Math FAQ on Large Numbers, or Russ Rowlett's Names for Large Numbers at http://www.unc.edu/~rowlett/units/large.html and check your dictionary as well!) So I would expect the missing prefixes to come from Latin "decem" (10), "viginti" (20), "triginta" (30), and "quadraginta" (40). The "gen" part of your words parallels the "gint" part of the normal number prefixes, and means "tens"; for example, my dictionary says the Latin "quinquageni" meaning "fifty each" comes from "quinquaginta" meaning meaning "fifty".
This implies that the words listed above parallel the anniversary names quinquagennial, sexagennial, septuagennial, octogintennial, and nonagintennial. Note that the last two have “int” inserted, relative to Wikipedia’s words.
I did a Web search to find pages that might list Latin words of this form, and found http://www.geocities.com/Athens/Forum/6946/distributive.html which tells me that the Latin words are "deni" (10), "viceni" (20), "triceni" (30), and "quadrageni" (40); so if the missing words existed, they would probably be denarian (teen) vicenarian (twenty-something) tricenarian (30+) quadragenarian (40+)
This agrees with my mention above of “denarius”, meaning “in ten parts”..
Checking my dictionary, I don't find these, though the last can be found on the Web, but we don't need these words since under-50's are not noteworthy. A 100-year-old is a centenarian; I don't know of any standard way to form words for 110 and up. Perhaps, from the Latin, "centenidenarian" would do.
It happens that I was an under-50 then (almost 49), and so “not noteworthy”; now I am a septuagenarian!
Sizes of groups: septuplets, etc.
Turning from ages to groups of items or people, here is a question from 2003:
Naming Nine Things What is the correct name for nine things collectively? I can only fine the answer up to 7, septuplet, which has been highly publicized with the McCoy babies. I am guessing nonet because non as in nonagon represents a nine-sided figure.
I answered:
Hi, Connie.
You've got the right basic idea, though our FAQ lists enneagon rather than nonagon, because "non-" is the Latin prefix for 9 while "ennea-" is the Greek prefix, which fits better with the Greek "-gon".
My dictionary (American Heritage) lists "octuple," "nonuple," and "decuple," so the natural thing is to add a "t" to each to make the form you want for a set of babies:
triplet
quadruplet
quintuplet
sextuplet
septuplet
octuplet
nonuplet
decuplet
We’ll look at Greek prefixes next time, since we don’t really need them here.
I notice my dictionary doesn't even list "septuplet," probably because there hadn't been any when it was published; but "sextuplet" is listed as formed by combining "sextuple" with the ending of "triplet," supporting this assumption. Even m-w.com lists only up to sextuplet, and it doesn't include octuple or nonuple but does have decuple.
Merriam-Webster does now list septuplet, octuplet, nonuplet, decuplet, as well as the forms without the final t.
In math, the corresponding term would just be "9-tuple"; why use words when numbers will do? In music, you would use "sextet," "septet," "octet," "nonet"; these are all listed in m-w.com.
Mathematicians are more practical than you may realize!
Groups of books: quadrilogy or tetralogy?
A few months later we got a similar question:
Trilogy, Tetralogy... If there are ordinal number systems like 1st, 2nd, 3rd, why isn't there a numbering system for groups like trilogies? I've heard of quintologies and hexologies but these words don't appear in the dictionary, (and I've checked many). If a trilogy is possible, why not a quadrilogy? In the dictionary a trilogy is defined as a series or group of three. But I can't find any terms for a group of four, five, six, seven, etc. Are there terms for number groups other than three?
Trilogy is a well-known word; can it be extended like our other groups above?
Again, I answered:
Hi, David. There are several different sets of terms for groups of three, depending on what you are counting: "trilogy" for books, "trio" for musicians or other people, "triplet" for children or generic groups, "triple" for numbers, "triad" for musical notes and so on. Each of these types of words can be found for other numbers: 3 trio triplet triple triad 4 quartet quadruplet quadruple tetrad 5 quintet quintuplet quintuple pentad ...
Note that the first three columns use the Latin prefixes we’ve focused on, but the last use Greek instead. “Tri-” is the same in both systems, but everything else is different. I could have added a row for 2: duo, twin, double, ? There’s more variation for small numbers.
But the “-logy” in “trilogy” is from Greek for “word”, which is also used to mean “study of”, as in theology. So using Latin prefixes is not quite right:
As for four books, considering the fact that trilogy comes from Greek roots, the proper word would be not "quadrilogy" but "tetralogy"; and in fact my dictionary lists that. It does not, however, list "pentalogy" for five books. The following gives one of these possible lists: Naming Nine Things http://mathforum.org/library/drmath/view/62004.html This lists the Latin and Greek prefixes used to make such words: Prefixes in Math http://mathforum.org/library/drmath/view/57196.html
We’ve seen both of those above.
David’s words “quintology” and “quadrilogy” do appear to be in use, perhaps more than “pentalogy” and “tetralogy”, but not in dictionaries; but “hexology” (and the Latin “sexology”) both tend to mean something very different. So here’s a list of book-words in actual use:
2: duology
3: trilogy
4: quartet, quadrilogy (“nonstandard)”, tetralogy
5: quintet, quintology (not in dictionaries), pentalogy (but not of books!)
Our names for numbers come (mostly) from Latin, too. We’ll look at them next; and then turn to Greek roots.