Hide/remove an existing suggestion (lightbulb) icon on form
1. Navigate to your form/record
2. Right click on the field with the suggestion icon and click configure "Dictionary" (For example short description in above screesnhot)
3. On Choice List, Select Drop Down= None
Alternatives will be to use DOM manipulation (which is beyond the scope of support and not recommended by support ) to remove the icon or create a new field for the Short Description.