I apologize if this is something trivial, but I struggle to find some reliable explanation regarding this issue. Understanding the nuances in the journal naming system would help me better categorize and search journals that suit me.
There is no reliable way to use the name to conclude about the eminence of a journal. There are some heuristics, though:
IEEE Transactions are typically supposed to be the flagship journals for a broader field. Quality between different transactions varies, but from the top of my head I cannot think of an IEEE transactions journal that is really bad.
IEEE magazines (IEEE Software, IEEE Internet Computing, IEEE Computer, etc.) are also mostly very well-respected, but their scope is entirely different. They publish short papers written for a broad audience. They are heavily copy-edited (for instance, the copy editor will typically re-draw all figures in a common style across all papers in an issue), and they tend to have a large impact (because these magazines are circulated very widely). However, due to limited size, they are often scientifically more shallow than transactions papers.
Other journals, that fall into neither category, vary in quality and esteem (though they are typically weaker than the relevant transactions in the field). Their scope is typically more narrow than transactions, but the opposite can also be true.