The word "densen" refers to something that is thick or dense. Therefore, some antonyms for "densen" would include words that describe things that are thin or sparse. Such antonyms could include words like "light," "thin," "rare," or "sparse." When used in context, these words could describe different things, such as a light mist instead of a dense fog or a sparse population instead of a densely populated area. It is important to note that antonyms for "densen" may vary depending on the context and usage of the word.