If you are writing a report on climate change, and ignore evidence that the earth is warming, the paper might be called tendentious. Tendentious means promoting a specific, and controversial, point of view.
When something is tendentious, it shows a bias towards a particular point of view, especially one that people disagree about. It shares a root with the word, tendency, which means leaning towards acting a certain way. If you have the tendency to talk in a tendentious manner about politics, people might tend to avoid you at parties.
