# What Greek letters do we use? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [August 22, 2020, 9:02pm UTC](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776 "2020-08-22T21:02:48Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![BigT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bigt/32/12044_2.png) [@BigT](https://boards.straightdope.com/u/BigT)\ **Post date:** [August 23, 2020, 3:48am UTC](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776/21 "2020-08-23T03:48:17Z")
> [@Roderick\_Femm](#): > > Isn’t theta used in some way in scientology? Lambda used to be a pretty common sort-of-secret reference to being gay, before gay lib, I don’t know what the status is these days.  I only knew about thetans, but it seems that does indeed come from the Greek letter theta. > **[Thetan | Cleared Theta Clear](https://en.wikipedia.org/wiki/Thetan#Cleared_Theta_Clear)** > > Even beyond the Operating Thetan levels comes the "Cleared Theta Clear", a godlike state which Hubbard describes this way: ---
**Author:** ![Shalmanese](https://avatars.discourse-cdn.com/v4/letter/s/45deac/32.png) [@Shalmanese](https://boards.straightdope.com/u/Shalmanese)\ **Post date:** [August 23, 2020, 4:19am UTC](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776/22 "2020-08-23T04:19:43Z")
It might be quicker to list all the greek letters not in common use. To my mind, they’re: Ϝϝ (digamma) Ηη (eta) Νν (nu) Ξξ (xi) Are any of these used in an area that an average user of English may encounter? ---
**Author:** ![Thudlow\_Boink](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/thudlow_boink/32/320_2.png) [@Thudlow\_Boink](https://boards.straightdope.com/u/Thudlow_Boink)\ **Post date:** [August 23, 2020, 4:22am UTC](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776/23 "2020-08-23T04:22:06Z")
> [@StarvingButStrong](#): > > I ran across sigma a lot in Calculus class and probability studies. Capital sigma is used for summation notation. Lower-case sigma is used for standard deviation. And mu is the symbol for population mean. Epsilon is commonly used in theoretical math for an arbitrarily small positive number, although that doesn’t make it “common use” generally.I had Calculus in high school from a teacher who loved the theoretical approach, and we saw lots of delta-epsilon proofs. ---
**Author:** ![Ruken](https://avatars.discourse-cdn.com/v4/letter/r/f475e1/32.png) [@Ruken](https://boards.straightdope.com/u/Ruken)\ **Post date:** [August 23, 2020, 2:25pm UTC](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776/24 "2020-08-23T14:25:36Z")
Yeah I’m surrounded by scientists and engineers, so my sense of “common” gets skewed. * * * > [@running\_coach](#): > > :flees: When come back . . . . ---
**Author:** ![Marvin\_the\_Martian](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/marvin_the_martian/32/2898_2.png) [@Marvin\_the\_Martian](https://boards.straightdope.com/u/Marvin_the_Martian)\ **Post date:** [August 23, 2020, 5:31pm UTC](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776/25 "2020-08-23T17:31:09Z")
Omega is used as the abbreviation for “ohms”. ---
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [August 23, 2020, 5:48pm UTC](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776/26 "2020-08-23T17:48:00Z")
> [@Tabco](#): > > I’ve seen the term “beta” used to refer to people (mostly males) who are shy, introverted, and basically the opposite of alpha males. Beta is not too bad, though. Wouldn’t they be at least zeta or eta males? ETA > [@BigT](#): > > I’ve actually even heard gamma males in some instances. Unlike betas, they aren’t even interested in becoming alpha. Ah, ninjaed. ---
**Author:** ![Napier](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Napier](https://boards.straightdope.com/u/Napier)\ **Post date:** [August 23, 2020, 7:45pm UTC](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776/27 "2020-08-23T19:45:12Z")
> [@Ruken](#): > > When come back . . . . I saw what you did there. ---
**Author:** ![mixdenny](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mixdenny/32/2962_2.png) [@mixdenny](https://boards.straightdope.com/u/mixdenny)\ **Post date:** [August 23, 2020, 11:59pm UTC](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776/28 "2020-08-23T23:59:06Z")
> [@Thudlow\_Boink](#): > > Capital sigma is used for summation notation. Lower-case sigma is used for standard deviation. And mu is the symbol for population mean. But in these cases and others mentioned the letter is just mathematical notation. The word has not entered our language as something. I realize Pi fits that category as well it is just much more common. ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [August 24, 2020, 12:25am UTC](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776/29 "2020-08-24T00:25:01Z")
> [@Shalmanese](#): > > It might be quicker to list all the greek letters not in common use. > > To my mind, they’re: > Νν (nu) Nu, you obviously don’t speak much yiddish. ---
**Author:** ![Shalmanese](https://avatars.discourse-cdn.com/v4/letter/s/45deac/32.png) [@Shalmanese](https://boards.straightdope.com/u/Shalmanese)\ **Post date:** [August 24, 2020, 4:55am UTC](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776/30 "2020-08-24T04:55:37Z")
> [@mixdenny](#): > > But in these cases and others mentioned the letter is just mathematical notation. The word has not entered our language as something. I realize Pi fits that category as well it is just much more common. “Six Sigma” as a quality control methodology has definitely entered enough into the language to count in my mind. ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [August 24, 2020, 11:07am UTC](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776/31 "2020-08-24T11:07:15Z")
> [@Typo\_Knig](#): > > I still see iota in crossword puzzles, usually related to the phrase “every iota and jot”. Interestingly, the word jot derives from iota. ---
**Author:** ![Apollon](https://avatars.discourse-cdn.com/v4/letter/a/e47774/32.png) [@Apollon](https://boards.straightdope.com/u/Apollon)\ **Post date:** [August 24, 2020, 5:42pm UTC](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776/32 "2020-08-24T17:42:17Z")
Alpha radiation (produced during radioactive decay). alpha strike (the first salvo that is fired in a battle). Delta wings (airplanes wiht triangular wings). Kappa (a trademark for sports apparel). Lambda (a symbol used by gay males). Rho (radius). Sigma (mathematical sum). Phi (angle in geometry). Psi (often used by pseudoscientists to symbolise extrasensory abilities). ---
**Author:** ![iamthewalrus\_3](https://avatars.discourse-cdn.com/v4/letter/i/258eb7/32.png) [@iamthewalrus\_3](https://boards.straightdope.com/u/iamthewalrus_3)\ **Post date:** [August 24, 2020, 5:53pm UTC](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776/33 "2020-08-24T17:53:17Z")
Lambda is used in computer science. Lambda calculus is a mathematical framework related to computing theory. It has started to enter business names, for example [https://lambdaschool.com/](https://lambdaschool.com/) Alpha and Beta are used in investing to refer to different ways to earn returns. ---
**Author:** ![Ynnad](https://avatars.discourse-cdn.com/v4/letter/y/4491bb/32.png) [@Ynnad](https://boards.straightdope.com/u/Ynnad)\ **Post date:** [August 24, 2020, 6:11pm UTC](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776/34 "2020-08-24T18:11:21Z")
> [@Colibri](#): > > But remember, pie are not square, pie are round. After many, many years I finally got to use that one as a trainee in an online training webinar a few weeks ago. I also added that cornbread are square. It was one of the highlights of my entire life. ---
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [August 24, 2020, 6:51pm UTC](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776/35 "2020-08-24T18:51:34Z")
> [@iamthewalrus\_3](#): > > Alpha and Beta are used in investing to refer to different ways to earn returns. As are other Greek letters like gamma, delta, rho, theta, etc. Investors, oddly, seem to think there are Greek letters with names like Vega, zomma, vera, veta, and more 🙂 ---
**Author:** ![StarvingButStrong](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/starvingbutstrong/32/335_2.png) [@StarvingButStrong](https://boards.straightdope.com/u/StarvingButStrong)\ **Post date:** [August 24, 2020, 8:35pm UTC](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776/36 "2020-08-24T20:35:48Z")
> [@Ynnad](#): > > > [@Colibri](#): > > > > But remember, pie are not square, pie are round. > > After many, many years I finally got to use that one as a trainee in an online training webinar a few weeks ago. I also added that cornbread are square. It was one of the highlights of my entire life. Nuh-uh. I always bake mine in a ROUND skillet. ---
**Author:** ![Ynnad](https://avatars.discourse-cdn.com/v4/letter/y/4491bb/32.png) [@Ynnad](https://boards.straightdope.com/u/Ynnad)\ **Post date:** [August 24, 2020, 8:40pm UTC](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776/37 "2020-08-24T20:40:52Z")
> [@StarvingButStrong](#): > > Nuh-uh. I always bake mine in a ROUND skillet. But don’t you cut into squares to serve it. I have never seen cornbread served in pie-shaped pieces. ---
**Author:** ![Thudlow\_Boink](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/thudlow_boink/32/320_2.png) [@Thudlow\_Boink](https://boards.straightdope.com/u/Thudlow_Boink)\ **Post date:** [August 24, 2020, 9:50pm UTC](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776/38 "2020-08-24T21:50:12Z")
> [@Apollon](#): > > Lambda (a symbol used by gay males) How come? ---
**Author:** ![DinoR](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dinor/32/2821_2.png) [@DinoR](https://boards.straightdope.com/u/DinoR)\ **Post date:** [August 24, 2020, 10:11pm UTC](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776/39 "2020-08-24T22:11:24Z")
> [@mixdenny](#): > > But in these cases and others mentioned the letter is just mathematical notation. The word has not entered our language as something. Six Sigma certainly entered our language as more than just notation. It is a reference to six standard deviations. ---
**Author:** ![Tinmansd](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tinmansd/32/3618_2.png) [@Tinmansd](https://boards.straightdope.com/u/Tinmansd)\ **Post date:** [August 24, 2020, 11:47pm UTC](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776/40 "2020-08-24T23:47:43Z")
In cosmology, lambda is the symbol for the cosmological constant to account for the expansion of space (and how we can see light from a galaxy 40 billion light years away even though the big bang was less than 14 billion years ago–how did that galaxy get so far away so fast? The Incredible Expanding Universe!) [Previous page](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776.md?page=1) [Next page](https://boards.straightdope.com/t/what-greek-letters-do-we-use/918776.md?page=3)