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Lots of symbols have their pronunciations. For instance, "$\tbinom {n}{k}$" is pronounced "$n$ choose $k$", and "$\forall$" is pronounced "for all".

The symbol "$\mapsto$" is used to represent a mapping, as in

$$x \mapsto f(x)$$

How to pronounce this symbol?

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JJJohn
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    I think "maps to" is the most common. – lulu Jul 29 '19 at 22:15
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    in fact, $\mapsto$ maps to $\mapsto$ – J. W. Tanner Jul 29 '19 at 22:17
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    I read it “$x$ goes to $f(x)$” – Lubin Jul 29 '19 at 22:33
  • If you know what it means you can pronounce it with any words that describe it. I personally use "maps to". If you are assuming there is verbal shorthand like $\partial x$ is "dee ecks" then... well, I don't think "maps to", at two very short syllables, needs any verbal shorthand – fleablood Jul 29 '19 at 23:18
  • I'm going to argue that $n\choose k$ and $\forall$ are not pronounced "$n$ choose $k$" and "for all" but that they are notation for "$n$ choose $k$" and "for all". And $\mapsto$ is notation for "$x$ gets mapped to $f(x)$". Or if you are short of breath "$x$ goes to $f(x)$" or "$x$ maps to $f(x)$". Or if you aren't into the whole brevity thing "the value $x$ is mapped by the function $f$ into its image $f(x)$". – fleablood Jul 29 '19 at 23:24
  • @Lubin, interesting. I always say "goes to" for things like $x_n\to x$. – The Count Jul 30 '19 at 01:10

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There's no fixed pronunciation - I've heard each of "maps to," "goes to," "is sent to," and further variations.

Keep in mind that there are lots of mathematical symbols with no fixed pronunciation: for example, "$\forall$" is pronounced as each of "For all," "For every," "For any," or "For each" with reasonable frequency (although personally I think the first two are the best choices and I strongly object to "For any").

Noah Schweber
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    What's your strong objection to "For any"? – Mars Plastic Jul 29 '19 at 23:19
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    The word any sometimes means all and sometimes means some and is hence ambiguous. Sometimes authors try to avoid the ambiguity by italicizing the word, but that doesn’t really help. – RobPratt Jul 30 '19 at 00:35
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    The word “any” is a problem word in English, and should be avoided in mathematical discourse. – Lubin Jul 30 '19 at 19:29