Deleting an album in Photos

In Photos for Mac

Right click on the album in the sidebar and select 'Delete'

Go to photos-on the top right of the screen tap on see all and then again same place edit. Now you will see the option to delete the album. However, please note this will only delete the album from your library and the photos stored on your phone or icloud.

Good luck!

I believe that's a reference to Photos for iOS (iPad and iPhones)