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Age Classifications

Date: 08/24/2001 at 14:55:38
From: Scott Ingwersen
Subject: Age classifications (i.e. septuagenarian)

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

Date: 08/24/2001 at 16:46:37
From: Doctor Peterson
Subject: Re: Age classifications (i.e. septuagenarian)

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   

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". 

I did a Web search to find pages that might list Latin words of this 
form, and found   

which tell 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+)

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.

- Doctor Peterson, The Math Forum   

Date: 12/27/2001 at 06:15:40
From: Anthony Brancato
Subject: Age Classifications

Those 110 years old and up (no upper limit) are now referred to as 
"supercentenarians" (the first use of this word appears to have 
cropped up in 1991, in a book entitled _Generations_ by William 
Strauss and Neil Howe).  

Also, "quadragenarian" meaning someone in their 40s, used to appear 
in dictionaries until about 30 years ago, when it was dropped in most 
places.  I have never run across an individual word describing any  
age decade younger than 40.
Associated Topics:
Elementary Definitions
Elementary Large Numbers
Middle School Definitions

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