Q:

What does a */* mean in a sentence

What does a / mean in a sentence like, "They read/reviewed the books they have." I can't find an answer to this question, but only get opinion which is what I do not need.

A:

To be very clear, my understanding is that a / (slash) is just an easy way or symbol of saying "and or or" (an example I could've used there is and/or!)
In your example, the sentence is just meaning:

They read and/or reviewed the books they have.

If you want to find a clearer definition, you could also call the "/" character a virgule. There are many other names, but these are the most popular.
Grammar Definition - (http://grammar.about.com/od/rs/g/slashterm.htm)

