# Mathematical Symbols

When reading mathematical papers or books, I often encounter symbols and I don’t know what to call them. Some of them are obviously Greek letters, but others I really have no clue. Some look like really fancy versions of normal letters.

Is there some resource that tells me what to call all commonly used mathematical symbols?

http://en.wikipedia.org/wiki/Mathematical_symbols

Should give you all you need. Mostly the symbols are called “the ‘what the symbol does’ symbol”, but clicking on the link for the operation will in most instances tell you what the symbol is called.

This is pretty far from comprehensive. If you run into a symbol not in there, use Detexify to find the LaTeX source for it, and then either Google or ask here for the definition.

That won’t always work. I make frequent use of a symbol that is roughly --o (without spaces) that is generally called “lollipop”. I doubt if knowing the source cde for it will help. Sometimes you are on your own and just give it a suggestive name for your own use.

If you encounter it online and it’s not an image, usually you can directly copy and paste it into a google or wiki search. Also, the ‘see also’ section covers a lot not in the main part of http://en.wikipedia.org/wiki/Table_of_mathematical_symbols

Wasn’t there this one site that let you draw the symbol, and it would identify the LaTex code for it (which usually includes the name?)

I do have to ask the OP a question though: why are you encountering so many mathematical formulas with symbols you don’t understand? And what good is merely knowing what they are called going to do?

For me, random browsing* brings up a few formula that I only understand what they’re trying to do at best (and often not even that). Knowing the names of the symbols makes it a lot easier to ask my math and engineering friends what’s going on without resorting to, “one squiggly next to another.”

*- Wikipedia is especially good for (bad at?) this. A couple links into a scientific article and you need a couple semesters of calculus to decipher the page. Forex, Gauss’s law.

Yes. Other than this, there are mathematical symbols that I use all the time without knowing what to call them.

For example, the fancy letter d used for partial differentiation: when I have to pronounce it, I say “the partial derivative of,” but if I have to describe it, I can’t do much better than “funny-looking d.”

i most frequently have heard that called ‘curly d’

0x2202 8706 PARTIAL DIFFERENTIAL ∂ http://www.ssec.wisc.edu/~tomw/java/unicode.html

Most of my profs (and consequently, I), call it “partial-d”, so ∂x/dt would be said as “partial d x d t”.

A few profs get lazy and call it “del”, but I think that’s usually when they are actually expanding a Laplacian or something.