The Parent Editor displays the immediate parents of the current sub-selection term:
The name and ID of the sub-selected term appear at the top of the panel. Each additional line in the display represents a parent link from the currently selected term to another term. The fields in each line are:
To add a new parent link to the selected term, drag the parent term onto the "Local-select other terms and drop here to add new parents" panel. A new link will be added with the dropped term as the parent, and is_a as the relationship type. Change the relationship type as needed.
Note that you have to drag the desired new parent from an Ontology Tree Editor that is in local selection mode, because you don't want the global selection to change. The most convenient way to do this is to have two Ontology Tree Editor panels open, with one in global and the other in local mode. Select the child in the global tree editor panel (which makes it the selected term in the Parent Editor), then drag the desired new parent from the local tree editor panel into the Parent Editor. To add a parent using a single Ontology Tree Editor panel, select the child with the OTE in global mode, then change to local mode before dragging the new parent.