Controlled vocabulary is a term used to refer to a set of predefined terms or phrases used to index or categorize information. This type of vocabulary is often used in libraries, archives, and museums, as well as in online databases. Some synonyms for controlled vocabulary include standardized vocabulary, controlled indexing, and controlled terms. These synonyms share the same meaning and are used interchangeably in the field of information management and organization. By using a controlled vocabulary, data can be organized in a consistent and precise manner, making it easier for users to find what they are looking for.