Because of a lapse in government funding, the information on this website may not be up to date transactions submitted via the website may not be processed, and the agency may not be able to respond to inquiries until appropriations are enacted.

The NIH Clinical Center (the research hospital of NIH) is open. For more details about its operating status, please visit

Updates regarding government operating status and resumption of normal operations can be found at

NCI Dictionary of Cancer Terms

  • Resize font
  • Print
  • Email
  • Facebook
  • Twitter
  • Google+
  • Pinterest

The NCI Dictionary of Cancer Terms features 8,188 terms related to cancer and medicine.

We offer a widget that you can add to your website to let users look up cancer-related terms. Get NCI’s Dictionary of Cancer Terms Widget.

reference values
(REH-frents VAL-yooz)
In medicine, a set of values that a doctor uses to interpret a patient’s test results. The reference values for a given test are based on the results that are seen in 95% of the healthy population. Sometimes patients whose test results are outside of the reference values may be healthy, and some patients whose test results are within the reference values may have a health problem. The reference values for a test may be different for different groups of people (for example, men and women). Also called normal range, reference interval, and reference range.