<p>Astro comes from the greek <code>άστρο</code> which not only means star but has a more general meaning that includes any small dot in the night sky (see <a href="https://en.wiktionary.org/wiki/%CE%AC%CF%83%CF%84%CF%81%CE%BF#Greek" rel="nofollow noreferrer">https://en.wiktionary.org/wiki/%CE%AC%CF%83%CF%84%CF%81%CE%BF#Greek</a> for details)</p>

<p>In today's language it still has a quite broad meaning:</p>

<p>Oxford English dictionary (<a href="https://www.oed.com/view/Entry/12240?isAdvanced=false&amp;result=2&amp;rskey=LlaQB9&amp;" rel="nofollow noreferrer">https://www.oed.com/view/Entry/12240?isAdvanced=false&amp;result=2&amp;rskey=LlaQB9&amp;</a>): </p>

<blockquote>
  <p>Forming terms relating to stars, other celestial objects, or outer space.</p>
</blockquote>

<p>Merriam Webster (<a href="https://www.merriam-webster.com/dictionary/astr-" rel="nofollow noreferrer">https://www.merriam-webster.com/dictionary/astr-</a>)</p>

<blockquote>
  <p>: star : heavens : outer space : astronomical </p>
</blockquote>

<p>Conclusion: Sheldon <em>and</em> Raj are right</p>

CC BY-SA 4.0
2019-08-22T13:38:18.737Z
2019-08-22T13:38:18.737Z
samcarter_is_at_topanswers.xyz
<p>Astro definitely means star, hence astronomer, astrophysics,asteroid etc. Asteroid means star-like. Astronaut is a bit grandiose, as it means someone who journeys to the stars, which is something astronauts will never do. They have their work cut out to visit and explore some of the planets, asteroids and moons in our own solar system, and some of those will never be visited. No astronaut will ever land on Venus for example, though it is the nearest planet to us. To continue the star theme further, we also have asterisk, a star-like symbol, and aster, a kind of daisy, I'm sure there are more of them. The word comes from the Latin for star.</p>

CC BY-SA 4.0
2019-08-26T15:14:16.093Z
If it comes from Latin, then why do the Greeks knew astronomy? Latin did not exist at that time. You're wrong.
User123
CC BY-SA 4.0
2019-08-22T13:02:08.770Z
2019-08-22T13:02:08.770Z
Michael Walsby
<p>In the popular TV show <a href="https://bigbangtrans.wordpress.com/series-3-episode-04-the-pirate-solution/" rel="nofollow noreferrer">The Big Bang Theory Season 3, Episode 4</a>, Sheldon Cooper said that <em>astro</em> means star and Raj said <em>astro</em> means space, I got a little confused here, various websites and others are going 50-50 on the subject. What does <em>astro</em> actually means?</p>
<blockquote>
<p>Raj: No, no, no, no! That rate is much too low for what we’d expect from this collision. Do you understand that we’re talking about dark matter colliding in outer space?</p>
<p>Sheldon: Of course I understand. And who are you to tell me about outer space?</p>
<p>Raj: I’m the astrophysicist. Astro means space.</p>
<p>Sheldon: Astro means star.</p>
</blockquote>

CC BY-SA 4.0
2019-08-22T12:11:49.010Z
Yeah but @user36296 I've mentioned that many are saying different things about it, I need complete proof about the meaning of the word, cause even google dictionary says astro means:     relating to the stars or celestial objects.
    "astrodome"
        relating to outer space.
        "astrochemistry"
Tazpool
CC BY-SA 4.0
2019-08-22T12:18:05.330Z
Why do you think it is an either or question?
samcarter_is_at_topanswers.xyz
CC BY-SA 4.0
2019-08-22T14:44:29.447Z
Do you mean definitive in the sense of how it was used originally in Greek or what it is used for today?
called2voyage
CC BY-SA 4.0
2019-08-22T15:51:16.520Z
This might be better on English Language, as it is not about astronomy but about the meaning of prefix in the Language.
James K
CC BY-SA 4.0
2019-08-22T15:53:00.760Z
@JamesK That's what I was trying to get at.
called2voyage
CC BY-SA 4.0
2019-08-22T18:12:14.450Z
I'm voting to close this question as off-topic because the meaning can be easily found in a dictionary.
James K
CC BY-SA 4.0
2019-08-22T23:09:37.993Z
I'm voting to **leave this question open** because definitions of astronomy terms is absolutely on topic, and we shouldn't just use "off-topic" to close for any reason we feel like using it for. We have a terminology tag, let it be used.
uhoh
CC BY-SA 4.0
2019-08-23T00:15:01.527Z
That is my point. The question isn't asking about a technical term, but the meaning of a regular word/prefix in English.  The answers below don't draw on any knowledge of astronomy or technical language, only dictionary definitions.  There might be an ELU question on the use of the prefix.
James K
CC BY-SA 4.0
2019-08-23T07:44:24.430Z
"Astro" means star in latinic, not space. Astrophysics is the physics or the stars, the vacuum, galaxies and so on. So both have right.
peterh
CC BY-SA 4.0
2019-08-23T15:00:12.317Z
@peterh thank you very much
Tazpool
CC BY-SA 4.0
2019-08-26T13:19:52.570Z
@uhoh I agree that questions of terms usage in astronomy is on topic, but it is not clear whether this is actually a question of that nature or merely a question about the general usage of an English term--or a question about the etymology of a term. I have changed the close reason to unclear.
called2voyage
CC BY-SA 4.0
2020-03-07T21:51:28.420Z
You are both right. From the Oxford American Dictionary. Astro = relating to the stars, celestial objects, or outer space
Natsfan
CC BY-SA 4.0
2020-03-08T05:57:40.960Z
So @jmh it doesn't means space, huh?
Tazpool
CC BY-SA 4.0
2020-03-08T14:00:19.107Z
It does mean space!
Natsfan
CC BY-SA 4.0
2020-03-10T05:31:00.133Z
[Cosmos](https://en.wikipedia.org/wiki/Cosmos) is the Greek word for universe. When the Soviets started putting humans in outer space (the cosmos) they called them cosmonauts - universe travelers. Because of political doctrinal differences (capitalism versus communism) during the space race, the Americans used the word astronaut (star traveler) for the humans they put into outer space.
Fred
<terminology>
Does astro means space or stars
Tazpool
# Does astro means space or stars

(Asked by: username_0 on 2019-08-22)

In the popular TV show [The Big Bang Theory Season 3, Episode 4](https://bigbangtrans.wordpress.com/series-3-episode-04-the-pirate-solution/), Sheldon Cooper said that *astro* means star and Raj said *astro* means space, I got a little confused here, various websites and others are going 50-50 on the subject. What does *astro* actually means?

> Raj: No, no, no, no! That rate is much too low for what we’d expect from this collision. Do you understand that we’re talking about dark matter colliding in outer space?
>
> Sheldon: Of course I understand. And who are you to tell me about outer space?
>
> Raj: I’m the astrophysicist. Astro means space.
>
> Sheldon: Astro means star.

**Tags:** terminology

> **Comments:**
> **username_0**: Yeah but @user36296 I've mentioned that many are saying different things about it, I need complete proof about the meaning of the word, cause even google dictionary says astro means:     relating to the stars or celestial objects.     "astrodome"         relating to outer space.         "astrochemistry"  
> **username_1**: Why do you think it is an either or question?  
> **username_2**: Do you mean definitive in the sense of how it was used originally in Greek or what it is used for today?  
> **username_3**: This might be better on English Language, as it is not about astronomy but about the meaning of prefix in the Language.  
> **username_2**: @JamesK That's what I was trying to get at.  
> **username_3**: I'm voting to close this question as off-topic because the meaning can be easily found in a dictionary.  
> **username_4**: I'm voting to **leave this question open** because definitions of astronomy terms is absolutely on topic, and we shouldn't just use "off-topic" to close for any reason we feel like using it for. We have a terminology tag, let it be used.  
> **username_3**: That is my point. The question isn't asking about a technical term, but the meaning of a regular word/prefix in English.  The answers below don't draw on any knowledge of astronomy or technical language, only dictionary definitions.  There might be an ELU question on the use of the prefix.  
> **username_5**: "Astro" means star in latinic, not space. Astrophysics is the physics or the stars, the vacuum, galaxies and so on. So both have right.  
> **username_0**: @username_5 thank you very much  
> **username_2**: @username_4 I agree that questions of terms usage in astronomy is on topic, but it is not clear whether this is actually a question of that nature or merely a question about the general usage of an English term--or a question about the etymology of a term. I have changed the close reason to unclear.  
> **username_6**: You are both right. From the Oxford American Dictionary. Astro = relating to the stars, celestial objects, or outer space  
> **username_0**: So @jmh it doesn't means space, huh?  
> **username_6**: It does mean space!  
> **username_7**: [Cosmos](https://en.wikipedia.org/wiki/Cosmos) is the Greek word for universe. When the Soviets started putting humans in outer space (the cosmos) they called them cosmonauts - universe travelers. Because of political doctrinal differences (capitalism versus communism) during the space race, the Americans used the word astronaut (star traveler) for the humans they put into outer space.  

---

## 2 answers

### Answer by username_1 on 2019-08-22. Score: 4

Astro comes from the greek `άστρο` which not only means star but has a more general meaning that includes any small dot in the night sky (see <https://en.wiktionary.org/wiki/%CE%AC%CF%83%CF%84%CF%81%CE%BF#Greek> for details)

In today's language it still has a quite broad meaning:

Oxford English dictionary (<https://www.oed.com/view/Entry/12240?isAdvanced=false&result=2&rskey=LlaQB9&>):

> Forming terms relating to stars, other celestial objects, or outer space.

Merriam Webster (<https://www.merriam-webster.com/dictionary/astr->)

> : star : heavens : outer space : astronomical

Conclusion: Sheldon *and* Raj are right


---

### Answer by username_8 on 2019-08-22. Score: -2

Astro definitely means star, hence astronomer, astrophysics,asteroid etc. Asteroid means star-like. Astronaut is a bit grandiose, as it means someone who journeys to the stars, which is something astronauts will never do. They have their work cut out to visit and explore some of the planets, asteroids and moons in our own solar system, and some of those will never be visited. No astronaut will ever land on Venus for example, though it is the nearest planet to us. To continue the star theme further, we also have asterisk, a star-like symbol, and aster, a kind of daisy, I'm sure there are more of them. The word comes from the Latin for star.

> **Comments:**
> **username_9**: If it comes from Latin, then why do the Greeks knew astronomy? Latin did not exist at that time. You're wrong.  

---

