It is recommended that you create projects and subjects to build related groups of words. Any new term you enter into LookUp will automatically be grouped into the subject and project you have previously set as default on the button "Project and Subject".

If you want to set a default, click on "Project and Subject" and enter a new customer or conference name in the left field or select one of the already listed.

Do the same in the subject field on the right side.
You can break your subjects down into categories such as energy.windpower or energy.nuclear.plant etc.