If you are using the Gleam WordPress theme from Elegant Themes, and you have just installed it, you may see that the home page menu shows undefined instead of the actual menu as shown in the demo of Gleam WordPress theme.
The home page menu shows ‘undefined’ only when, you guessed it, the menu is undefined. To fix this issue, first go to epanel (Appearance > Theme Options) and click on Save button once. Reload the home page of your site to check if it resolves the issue.
If it doesn’t then make sure that you have created the custom menu correctly and have assigned it to a correct theme location.
If the custom menu is also setup correctly, and the home page of your site still shows undefined instead of menu, then go to Settings > Reading and select ‘your latest posts’ for Front page display settings and click on Save button.
This should resolve the issue. But please make sure to clear your browser’s cache and disable any caching plugins while you make these changes, otherwise you will not be able to see the changes as the site will keep showing the cached home page.