I think the factual answer to this is that, while some individuals may have their own personal “precise meanings” that distinguish between these symbols, there is no standard, official, or universally understood difference.
That’s because before computers, most people weren’t typing math expressions on a 1- line display format. They were hand writing expressions on paper or chalkboards.
There, people would offset divisions above and below a horizontal line.
The slash might have been used in typesetting like for formal reports. Journals and books had their own typesetting methods and weren’t constrained to one-line expressions.
Computers required the ability to write expressions linearly. Parentheses and brackets took on more frequent use, and / and * took on the necessary roles.
This all sounded much too late to me, and too much blamed on computers. So I went searching and found an interesting site on the earliest uses of symbols for fractions. The relevant part is this:
The diagonal fraction bar (also called a solidus or virgule) was introduced because the horizontal fraction bar was difficult typographically, requiring three terraces of type.
An early handwritten document with forward slashes in lieu of fraction bars is Thomas Twining’s Ledger of 1718, where quantities of tea and coffee transactions are listed, e.g. 1/4 pound green tea. This usage of the horizontal fraction bar was found by Hans Lausch, who believes there are likely even earlier occurrences.
Lausch has also found the horizontal fraction bar in Allgemeine Deutsche Bibliothek, a Berlin review journal which was started in 1765. A precise reference may be forthcoming.
The earliest instance of a diagonal fraction bar shown by Cajori (vol. 1, page 313) is in 1784, when a curved line resembling the sign of integration was used in the Gazetas de Mexico by Manuel Antonio Valdes.
In 1843, a curved line was used by Henri Cambuston in Definicion de las principales operaciones de arismetica (Cajori vol. 1, page 313)
In 1845, the use of the solidus was recommended by De Morgan in an article “The Calculus of Functions” published in the Encyclopaedia Metropolitana of 1845 (Cajori vol. 1, page 313).
In 1852, the solidus was used by Antonio Serra Y Oliveres in Manuel de la Tipografia Española (Cajori vol. 1, page 313).
So, versions of “/” being used in the 18th century, with mathematicians recommending its use by the mid-19th century.
But are we distinguishing between / used as a fraction bar and / used as a division symbol?
(Of course, mathematically, 1÷4 is the fraction 1/4, but I’ve never seen anyone write a fraction specifically as a fraction using the ÷.)
I haven’t gone to the sources, but note that the 1843 source is talking about arithmetic operations and the 1845 source is about calculus of functions, so would be talking about arithmetic operations on functions. I’m inferring they discussed division, not just fractions.
This caused me genuine confusion in my early career as an internal auditor, visiting our branches in Copenhagen for the first time.
Right. However you would be hard-pressed to find any use of ÷ at all in the mathematical or technical literature, as far as I know, which should be the answer to the OP’s question. It does indeed show up on the keyboard of some pocket scientific calculators, but I think the users can figure it out.
As far as * for multiplication, we can pin it to the development of the first higher-level computer language: FORTRAN. They couldn’t use X (computers didn’t have lower case letters at the time) because that would be a variable, so they adapted the orthographically closest non-alphanumeric symbol.