I'm thinking that you likely need to open the Index editor pod. Locate the keyword linking to this topic, then look in the "Topics For" area at the bottom of the Index pod. You should be able to change the name you see by editing it there.
Thanks, Rick! That worked.
You can see a list of all the places where a topic is referenced by right-clicking on the topic in the Project Manager pod and selecting Show > Topic References. The dialog box shows topics, ToC entries and index entries that reference the topic.
If you click on an index entry (with a key symbol) and click Edit, you can edit the Title field which will update what appears in the index. Similarly you can update ToC entries this way (the book icon). (On the downside, as soon as you click OK, both dialog boxes close and you have to right-click again. Feel free to submit a feature request. )
For topics, Edit will open the applicable topic and you'll have to manually find the reference.