The rows and columns for Blackboard Rubrics have default headings which you can easily change to meet your course needs.
Start out in the Create or Edit Rubric window.
Under the heading Rubric Details should be the Rubric Grid with all the default rows (Criteria) and columns (Levels of Achievement).
Next to any row or column heading, click the gray arrow and Edit. Type your new title and click Save.
Be sure to click Submit to save your work.