The word "palais" means a palace in French. If you want to use other synonyms for this word, you can consider using terms such as "château," "manoir," "maison de maître," "hôtel particulier," and "residence." These words have a similar meaning to palais as they all refer to grand and luxurious houses, although some have different connotations. Château is generally associated with a large country house or castle, while maison de maître refers to a master's house. Hôtel particulier denotes a townhouse that was built for affluent families, and residence denotes a prestigious dwelling or dwelling place. You can use these synonyms to add some variety to your writing and to express yourself more effectively.