In your app, press the 'Group' button to see a list of all the groups in the community. You will note that above the groups rests a slide menu with several options. slide to the 'My Groups' option where you will see the groups that you are the owner of. On the right hand side of each group you will note the 'More Options' menu (three horizontal dots). Once you press on it, you will see the option to delete the group.

Please note that deleting a group is irreversible.   

In your browser, press the 'Group' button to see a list of all the groups in the community. On the right sidebar you will see a filter option to view 'My Groups' where you will see the groups that you are the owner of. On the top right hand side of each group you will note the 'More Options' menu (three horizontal dots). Once you press on it, you will see the option to delete the group. 

Please note that deleting a group is irreversible.