Can you do a mock-up in InDesign of waht you want it to look like and take a screen capture? Use some real words so we get a feel for what is going on. You can embed the screen capture in a post using the camera icon on the web page:
I'm not quite sure from your description what you are trying to do. This looks like what I would call a Glossary, rather than an Index or Table of contents, and if that's the case it might be enough to just define the paragraph style as a numbered list.
There is some inconsistency in your example -- several of the listings have run-in headings while others have the heading on a separate line. In order to automate this you're going to need to adopt a consistent style.
In either case, this can be accomplished quite easily with paragraph styles. For run-in headings you would use a nested charachter style to bold the heading and nest it up to or through the character you use to separate the heading from the definintion, depending on if you want the spearator to match the heading or the definition.
For headings on a separate line you can use two paragraph styles, one for the heading and one for the definition, and put each part in a separate paragraph, or you can use the sem single style with a nested character style approach and use a forced line break to separate them. If you use two paragraphs for each listing, set the definition style as the "next style" for fo the headings, and the heading style as the next style for the definitions so they will cycle.