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Web Standard: Glossaries


A glossary is a list of terms and their associated definitions, usually related to a particular program or subject. In order to foster understanding, numerous EPA Programs make glossaries available on their web pages.

Terminology Services (TS) is a centralized approach for maintenance and display of glossaries at EPA.

Content Requirements

Please note: this standard does not apply to glossaries within or attached to a particular document, but rather stand-alone, web-based Program glossaries.

  • Glossaries must be managed in Terminology Services including glossaries that currently exist only on a web page. They may not be managed on a static HTML page, nor in a document attached to a web page (e.g. pdf).
    • Note: most EPA Program glossaries have already been loaded into Terminology Services.
  • For guidance on how to manage a glossary in Terminology Services, please refer to the Glossary Management Guide(10 pp, 3 MB)
  • For more information on managing your glossary in Terminology Services, including best practices for creating and maintaining glossaries, please see: Terminology Services References
  • Provide a link from your web page to your glossary within Terminology Services.
  • Review/update your glossary at least once a year.
  • Before creating a new glossary or revising an existing one, you may want to review the Terminology Services repository to determine if existing content can be used in creating or standardizing your glossary.


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About this Standard

All EPA public web content must adhere to the EPA Web Standards, the U.S. Web Design System guidelines, and the 21st Century Integrated Digital Experience Act.

Effective date: 02/08/2012
Date approved: 10/14/2020
Web Council review by: 10/14/2021 (or earlier if deemed necessary by the Web Council)