# Meaning of a Symbol

1. Oct 20, 2014

### ckirmser

I've run across a symbol on a NASA paper from 1984 that I am not familiar with and that I could not find in a web search.

It's a capital 'V' with a horizontal cross bar through its center. Any ideas?

2. Oct 20, 2014

### bhillyard

Was it an inverted upper case A? If so it might be the logic symbol meaning "for all".

3. Oct 20, 2014

### SteamKing

Staff Emeritus
Can you post an image of this symbol or provide a link to the paper?

4. Oct 21, 2014

### Staff: Mentor

Did it look like this?
$$\forall$$

5. Oct 21, 2014

### Staff: Mentor

What's it mean?

6. Oct 21, 2014

### Staff: Mentor

It means "for each" or "for all".

7. Nov 4, 2014

### ckirmser

Well, with what I've been doing, I had become accustomed to the nomenclature of a paper being right up there by the introduction or abstract. So, I finally came to the end of this NASA paper and discovered - ta daaa!

The nomenclature.

So, the symbol, V with a horizontal cross-bar (duplicated by going into Word, or some such, typing a capital V and clicking the strike-through button), anyway, that symbol stands for, "Volume of ion production region (m3)."

Still trying to learn what that is - I am, by no means, really understanding more than the concepts of this paper - so, I don't know what that is, though I kind of have a guess.

8. Nov 4, 2014

9. Nov 5, 2014

### LCKurtz

Nice. You give us a 125 page document but no hint on what page to look for your symbol.

10. Nov 5, 2014

### FeDeX_LaTeX

Just skimmed through it, there's a symbol matching his description first appearing at the bottom of page 30, in equation (12). Can't work out what it means though -- it appears again on page 38.

EDIT: Just checked the glossary at the bottom. It means "volume of ion production region", measured here in cubic metres.

EDIT 2: According to post #7, the OP has already discovered this...

Last edited: Nov 5, 2014