# Decade, century, millennium, ..? **URL:** \ **Category:** Factual Questions\ **Created:** [August 7, 2010, 10:48pm UTC](https://boards.straightdope.com/t/decade-century-millennium/549553 "2010-08-07T22:48:01Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![Rune](https://avatars.discourse-cdn.com/v4/letter/r/e68b1a/32.png) [@Rune](https://boards.straightdope.com/u/Rune)\ **Post date:** [August 7, 2010, 10:48pm UTC](https://boards.straightdope.com/t/decade-century-millennium/549553/1 "2010-08-07T22:48:01Z")
Decade is 10 years, century 100, millennium 1000 - is there a word for 10,000? ---
**Author:** ![Johnny\_L.A](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_l.a/32/1084_2.png) [@Johnny\_L.A](https://boards.straightdope.com/u/Johnny_L.A)\ **Post date:** [August 7, 2010, 10:55pm UTC](https://boards.straightdope.com/t/decade-century-millennium/549553/2 "2010-08-07T22:55:57Z")
Decamillenium? 😛 [According to this](http://en.wikipedia.org/wiki/Orders_of_magnitude_(time)#Years), it goes from millennium (1,000 years) to epoch (1,000,000 years). ---
**Author:** ![Diogenes\_the\_Cynic](https://avatars.discourse-cdn.com/v4/letter/d/e99b99/32.png) [@Diogenes\_the\_Cynic](https://boards.straightdope.com/u/Diogenes_the_Cynic)\ **Post date:** [August 7, 2010, 10:57pm UTC](https://boards.straightdope.com/t/decade-century-millennium/549553/3 "2010-08-07T22:57:37Z")
Decamillenium = 10,000 years Centamillenium = 100,000 years ---
**Author:** ![Polycarp](https://avatars.discourse-cdn.com/v4/letter/p/82dd89/32.png) [@Polycarp](https://boards.straightdope.com/u/Polycarp)\ **Post date:** [August 7, 2010, 11:00pm UTC](https://boards.straightdope.com/t/decade-century-millennium/549553/4 "2010-08-07T23:00:06Z")
Myriad, which functions both as noun and adjective, means “10,000” (not specifically years). So “[a] myriad [of] years”, with the “a” and “of” optional, would do the job. ---
**Author:** ![Diogenes\_the\_Cynic](https://avatars.discourse-cdn.com/v4/letter/d/e99b99/32.png) [@Diogenes\_the\_Cynic](https://boards.straightdope.com/u/Diogenes_the_Cynic)\ **Post date:** [August 7, 2010, 11:04pm UTC](https://boards.straightdope.com/t/decade-century-millennium/549553/5 "2010-08-07T23:04:22Z")
Also, if you’re curious it continues as follows: megennium = 1 million years decamegennium =10 million years centamegennium = 100 million years gigennium = 1 billion years I think only geologists ever really use these terms, though. ---
**Author:** ![Little\_Nemo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/little_nemo/32/3120_2.png) [@Little\_Nemo](https://boards.straightdope.com/u/Little_Nemo)\ **Post date:** [August 8, 2010, 12:05am UTC](https://boards.straightdope.com/t/decade-century-millennium/549553/6 "2010-08-08T00:05:01Z")
> [@Johnny\_L.A](#): > > According to this, it goes from millennium (1,000 years) to epoch (1,000,000 years). Is 2,000,000 years a tupoch? ---
**Author:** ![Polycarp](https://avatars.discourse-cdn.com/v4/letter/p/82dd89/32.png) [@Polycarp](https://boards.straightdope.com/u/Polycarp)\ **Post date:** [August 8, 2010, 12:13am UTC](https://boards.straightdope.com/t/decade-century-millennium/549553/7 "2010-08-08T00:13:32Z")
1,000,000,000 years is an eon (which I’ve never seen written æon _in this context_). It’s a specialized usage, of course. ---
**Author:** ![running\_coach](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/running_coach/32/15836_2.png) [@running\_coach](https://boards.straightdope.com/u/running_coach)\ **Post date:** [August 8, 2010, 12:17am UTC](https://boards.straightdope.com/t/decade-century-millennium/549553/8 "2010-08-08T00:17:00Z")
> [@Little\_Nemo](#): > > > [@Johnny\_L.A](#): > > > > According to this, it goes from millennium (1,000 years) to epoch (1,000,000 years). > > Is 2,000,000 years a tupoch? And 10,000,000 is a shakur. ---
**Author:** ![Mona\_Lisa\_Simpson](https://avatars.discourse-cdn.com/v4/letter/m/ce7236/32.png) [@Mona\_Lisa\_Simpson](https://boards.straightdope.com/u/Mona_Lisa_Simpson)\ **Post date:** [August 8, 2010, 4:28am UTC](https://boards.straightdope.com/t/decade-century-millennium/549553/9 "2010-08-08T04:28:45Z")
> [@runner pat](#): > > > [@Little\_Nemo](#): > > > > Is 2,000,000 years a tupoch? > > And 10,000,000 is a shakur. Takes a lot of balls to make that joke. :d&r ---
**Author:** ![Tom\_Tildrum](https://avatars.discourse-cdn.com/v4/letter/t/e95f7d/32.png) [@Tom\_Tildrum](https://boards.straightdope.com/u/Tom_Tildrum)\ **Post date:** [August 9, 2010, 2:08pm UTC](https://boards.straightdope.com/t/decade-century-millennium/549553/10 "2010-08-09T14:08:40Z")
> [@Johnny\_L.A](#): > > … to epoch (1,000,000 years). And if a lot happens during that million years, it’s an epic epoch. ---
**Author:** ![Alka\_Seltzer](https://avatars.discourse-cdn.com/v4/letter/a/c89c15/32.png) [@Alka\_Seltzer](https://boards.straightdope.com/u/Alka_Seltzer)\ **Post date:** [August 9, 2010, 2:34pm UTC](https://boards.straightdope.com/t/decade-century-millennium/549553/11 "2010-08-09T14:34:46Z")
Normal English would be to say “10 milliennia”. ---
**Author:** ![Canadjun](https://avatars.discourse-cdn.com/v4/letter/c/76d3ee/32.png) [@Canadjun](https://boards.straightdope.com/u/Canadjun)\ **Post date:** [August 9, 2010, 8:43pm UTC](https://boards.straightdope.com/t/decade-century-millennium/549553/12 "2010-08-09T20:43:51Z")
> [@Diogenes\_the\_Cynic](#): > > Decamillenium = 10,000 years > Centamillenium = 100,000 years The metric prefix for 100 is hecto, not centa. ---
**Author:** ![Diogenes\_the\_Cynic](https://avatars.discourse-cdn.com/v4/letter/d/e99b99/32.png) [@Diogenes\_the\_Cynic](https://boards.straightdope.com/u/Diogenes_the_Cynic)\ **Post date:** [August 9, 2010, 8:55pm UTC](https://boards.straightdope.com/t/decade-century-millennium/549553/13 "2010-08-09T20:55:56Z")
It’s not metric, it’s Latin. ---
**Author:** ![Bennett3207](https://avatars.discourse-cdn.com/v4/letter/b/c37758/32.png) [@Bennett3207](https://boards.straightdope.com/u/Bennett3207)\ **Post date:** [November 2, 2016, 10:24am UTC](https://boards.straightdope.com/t/decade-century-millennium/549553/14 "2016-11-02T10:24:16Z")
Going on what Diogenes the Cynic said, I’m pretty sure: **Year = 1 year Decade = 10 years Century = 100 years Millenium = 1,000 years Decamillenium = 10,000 years Centamillenium = 100,000 years Megennium = 1 million years Decamegennium =10 million years Centamegennium = 100 million years Gigennium = 1 billion years Decagigennium = 10 billion years Centagigennium = 100 billion years Terrennium = 1 trillion years Decaterrennium = 10 trillion years Centaterrennium = 100 trillion years petennium = 1 quadrillion years Decapetennium = 10 quadrillion years Centapetennium = 100 quadrillion years Exennium = 1 quintillion years Decaexennium = 10 quintillion years Centaexennium = 100 quintillion years Zettennium = 1 sextillion years Decazettennium = 10 sextillion years Centazettennium = 100 sextillion years Yottenium = 1 septillion years Decayottenium = 10 septillion years Centayottenium = 100 septillion years** However, this is just another post extended and I could be completely wrong:confused:. ---
**Author:** ![jtur88](https://avatars.discourse-cdn.com/v4/letter/j/e9c0ed/32.png) [@jtur88](https://boards.straightdope.com/u/jtur88)\ **Post date:** [November 2, 2016, 1:36pm UTC](https://boards.straightdope.com/t/decade-century-millennium/549553/15 "2016-11-02T13:36:39Z")
In India, everyday language uses lac (100,000) and crore (10,000,000) when referring to money. An Indian financier will say “ten lac” rather than “one million” rupees, and then “five crore” rather than “fifty million”. Commas are used differently for separators. Instead of $12,345,678 expressed as millions, it will be $1,23,45,678, and said "one crore, 23 lacs, 45 thousand "