If a Group was created in error or is no longer needed, it can be deleted/removed.
If a group is deleted, all of the Group's content and history will be deleted as well.
Deleting a Group
Click Groups or the People icon on the left menu.
Click View on the group would want to delete.
Near the top right, click the Delete button.
Checkmark the “I understand that this action cannot be undone” check box to confirm you understand it cannot be undone and then click the Delete button to delete the group.