The construction of a semantically associated computer search database is disclosed. A text catalog containing the text particulars and contents of a plurality of electronic documents, a term association database which joins text search terms with their semantic meanings or definitions, and a content association database which contains records associating text search terms and their contextual definitions in respect of individual electronic documents are used to in conjunction provide a text index in which it is possible to search based upon the actual definitions or meanings of certain text or terms within the electronic documents, reducing or refining query search result sets. A method of operating a search engine with the index in question, as well as other e-commerce methods employing the index as a refining tool are also disclosed.