The cars belong to the same category. Taxpayers fall into one of several categories. She competed for the award in her age category.Category definition, any general or comprehensive division; a class. See more.But for the whole of the day, there is no disguising it, you must put yourself in the same category with Mrs.Synonyms for category at Thesaurus.com with free online thesaurus, antonyms, and definitions. Dictionary and Word of the Day.