Guide to Guideline 3.1 Level 3 Success Criterion 3

3.1 L3 SC3

Key terms and important concepts

Text content

WCAG definition of text goes here]


Ready for use or service; usable

NOTE: [Note: The baseline impact analysis for guidelines and SC recommended that the phrase "is available]" be used in this and a number of other SC as a way to describe a "functional outcome." I am concerned that the phrase is vague and subject to intentional misinterpretation—e.g., a mechanism is available but we didn’t implement it." To avoid this, we may want to consider changing "mechanism is available" to something like "mechanism has been implemented" or "is available to the user."]


A word made from the initial letters of a name that contains several words. For example, NOAA is a word made from the initial letters of the National Oceanic and Atmospheric Administration in the United States. SNCF is a French acronym that contains the initial letters of the Societe National des Chemins de Fer, the French national railroad.


The shortened form of a word. For example, "Dr." is the abbreviation for the English word "doctor." "M." is the abbreviation for the French word "Monsieur."

Intent of this success criterion

The intent of this success criterion is to ensure that users can access the expanded form of acronymns and abbreviations.

Technology-Independent techniques for Guideline 3.1 L3 SC3

Editorial Note: In future Working Drafts, this section will contain links to relevant sections of General Techniques for WCAG 2.0. The information below is presented to indicate the types of material that are available.

There are several ways to address this success criterion.

Searching an online dictionary of acronyms

  • Provide a form that searches an online dictionary of acronyms in the language of the content.

  • Include a dictionary of acronyms and/or a glossary of acronyms and abbreviations in a "dictionary cascade," a list of dictionaries and other references to search for definitions of words or phrases the user has selected. This technique attaches a list of dictionaries to a delivery unit so that users can find definitions for all words in the text. The "cascade" lists the dictionaries and other reference materials in the order most likely to bring up the right definition. This controls the order to follow when searching for definitions. (See the Guide to GL 3.1 L3 SC1 for additional information.)

  • Provide the expansion of each acronym or abbreviation the first time it appears in the delivery unit. Note: If there are no online acronym dictionaries for the language of the content, authors will need to do at least one of the following:

    • Provide a glossary of acronyms and abbreviations used in the content.

    • Provide the expanded form of each acronym or abbreviation the first time it appears in the delivery unit.

Technology-Specific Techniques for Guideline 3.1 L3 SC3

HTML Techniques

Advisory techniques: going beyond Guideline 3.1 L3 SC3

Benefits: How Guideline 3.1 L3 SC3 helps people with disabilities

This success criterion helps people whose disabilities make reading difficult or impossible. These include:

Examples of Guideline 3.1 L3 SC3

Example 1: A dictionary search form.

A Web site includes a search form provided by an online acronym service. Users enter an acronym and the form returns a list of possible expansions from the sources that it searched.

Example 2: A medical Web site.

A medical website provides information for both doctors and patients. The site includes a set of cascading dictionaries. A very specialized medical dictionary is first, followed by a second medical dictionary for the general public. The cascade also includes a list of acronyms and abbreviations that are unique to the site, and finally there is a standard dictionary as well. The standard dictionary at the end of the list provides definitions for most words in the text. The specialized medical dictionary yields definitions of unusual medical terms. Definitions for words that appear in more than one dictionary are listed in the order of the cascade. The meaning of acronyms and abbreviations is provided by the list of acronyms and abbreviations.

Example 3: An abbreviation whose expansion is provided the first time the abbreviation appears in the content.

The name, World Wide Web Consortium," appears as the first heading on the organization’s home page. The abbreviation, "W3C," is enclosed in parentheses in the same heading.