Keyword vs. Subject Searching


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Sometimes it is beneficial to try a subject search on your topic, which can give you more precise results.  What is the difference between keyword and subject searching?

Subject Keyword

  • A subject heading search only searches in the subject/descriptor field. If you do not know a subject heading to search on, do a keyword search first. When you find a good resource, check out the subject headings listed in the record and use it as a gateway to find similar materials.  Note: you can combine subject headings and keywords in your search

  • A keyword search does not use a controlled vocabulary and will find your search terms in any number of descriptive fields (title, abstract, etc.). Before beginning a keyword search, spend a few minutes brainstorming synonyms and alternative spellings. A thesaurus can help with this process.
Quick Comparison

  • Narrow search (Retrieves potentially fewer items)
  • Searches only in the subject/descriptor field
  • Search terms must be selected from a controlled vocabulary list like the Library of Congress Subject Headings or a database’s thesaurus
  • High degree of relevancy
Quick Comparison

  • Broad Search (Retrieves a potentially large number of items)
  • Searches in any number of descriptive fields like title, subject, and/or document text
  • Search terms can be any concepts or words/phrases that you choose
  • High degree of inclusiveness


Examples of Keyword Terms

  • Native Americans
  • Cars
  • Movies or films
  • United States and civil war
Examples of Subject Headings

  • Indians of North America
  • Automobiles
  • Motion pictures
  • United States History Civil War, 1861-1865
Use When

  • A subject heading on your exact topic exists
  • Want precise results immediately
Use When

  • There is no subject heading for your topic (topic is very current)
  • Database does not allow subject searches
  • Subject headings are too broad or too specific