Automatic keyword search/linking

It would be absolutely huge for if there was a way to have a sort of link between key words (e.g. character names, place names, terms of art) and linked explanatory text, along with appearances of the text in the document. I take the idea from programming IDEs, in which references to function names can be moused-over or right-clicked to show the referenced function and its location. I’m thinking of right-clicking on a name and having the relevant references show up in other windows/sub-windows for instant referencing, or a keyboard shortcut when the cursor is in a key word.

Or maybe there’s already a way to do this and I just haven’t figured it out. All I know is that my neurotic test-engineer instincts make me always want to have previous references for every little thing available, and performing a separate text search each time is really disruptive. I don’t mind going through and making a little linked-document for each item, if it means I don’t have to do a lot of extra clicking to bring it back to visibility, along with an elegant way of bringing other uses (especially the first) into view.

I’m hoping that by designating things as keywords, any indexing would be lightweight and fast. I’ve been around enough to know things frequently aren’t as easy as they look, but those are my thoughts. And again, if there’s already a way to do this and I just haven’t recognized it, I look forward to suggestions.