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Naming Nine Things

```Date: 01/15/2003 at 09:41:22
From: Connie P. (Middle School Math teacher)
Subject: Naming nine things (like 3 is triplet)

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.
```

```
Date: 01/15/2003 at 10:16:48
From: Doctor Peterson
Subject: Re: Naming nine things (like 3 is triplet)

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
quintuplet
sextuplet
septuplet
octuplet
nonuplet
decuplet

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.

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.

If you have any further questions, feel free to write back.

- Doctor Peterson, The Math Forum
http://mathforum.org/dr.math/
```
Associated Topics:
Elementary Definitions