Other forms: banalized; banalizing; banalizes
To banalize something is to make it seem less important, especially through repetition. A comedy film that's set during World War I might banalize the real horrors of war.
To banalize is to make something that's actually important seem banal — boring, ordinary, or trivial. The story about the boy who cried wolf is a good example of this: by claiming to see wolves every day, the boy banalized the idea of encountering a dangerous animal, and no one believed him when he actually did see one. In the real world, the media is often accused of turning news into entertainment, banalizing serious issues in the process.