Is there a privilege in Oracle that lets a user view or not view the list of objects in another schema?
Oh, yes. Lots of them. :-)
I've got a user where I've given them select rights to a view in another user's schema.
I'm guessing you're still at the "Users are important to Security" stage (Trust me; they're not).
I'd strongly suggest using Roles to confer privileges. Then, when a given User moves on and someone comes in to replace them, you just grant them the Role and everybody's happy. Without this, you'll probably have to try and rebuild all this from scratch (because you'll have deleted the first Users account, and all their privileges, when they left!)
However, they don't seem to be able to see that view in their client (think they are using Oracle's SQL Developer).
This might be as simple as they don't know where to look in that client!
Multiple schemas throws a lot of people when they start with Oracle.
When they fire up SQL Developer, they can see all the objects that their account owns.
To find objects owned by any other account, they have to rummage through the "tree" to find the "Other Users" entry, expand that, find the user in question and all the objects owned by that account (that they have privileges to see) will appear there.
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+ Other Users <-- This is the Trouble-maker
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