A federal government Website managed by the U.S. Department of Health and Human Services
200 Independence Avenue, S.W.
Washington, D.C. 20201
Our glossary provides easy-to-understand definitions for many of the terms you’re likely to see as you’re learning about vaccines.
Looking for an abbreviation? Get a list of the vaccine-related acronyms and abbreviations used on our site and in vaccination records.
Last reviewed: January 2018