Apple - How do I get a lone missing app to appear in Spotlight searches?
While this does not directly answer as to why that particular app does not appear in Spotlight, nonetheless as a workaround, try the following:
Explicitly exclude the App, via drag and drop from Finder, into System Preferences > Spotlight > Privacy, and then close/reopen Spotlight preferences and remove the App by selecting it, then click the minus button [-] at the bottom left of the list window.
The App should now appear in Spotlight, however it may disappear again if the root cause is triggered again.
I was facing the same issue with Todoist and Microsoft Outlook. The answer above didn't solve the problem for me on MacOS Sierra 10.12.6, as you can only exclude whole folders now in the Spotlight Privacy tab. I tried that, but it didn't help. However a similar solution worked for me:
- System Preferences > Spotlight > Search Results
- Untick 'Applications'
- Close the settings
- System Preferences > Spotlight > Search Results
- Tick 'Applications'