Define uncategorized. uncategorized synonyms, uncategorized pronunciation, uncategorized translation, english dictionary definition of uncategorized. adj. 1. Uncategorized: 1 adj not categorized or sorted synonyms: uncategorised , unsorted unclassified not arranged in any specific grouping. Categorize definition, to arrange in categories or classes; classify. see more. To change your default post category in wordpress, do the following: hover over “posts” in the left sidebar and click “categories” in the flyout menu. hover over “uncategorized” and click the “edit” link that appears below the category name. type your new default category (with a lowercase letter) in the slug field. What is the uncategorized category? in wordpress, when it comes to organizing content, tags and categories are two outstanding and commonly used features. a category refers to a taxonomy, which is used to group and select related posts together.