Abbreviations
Tier 1 · The normative floor
Baseline compliance
What the normative text of WCAG 2.2 requires, and nothing more. Only a failure of this tier is a WCAG failure.
The bare minimum
A mechanism is available for identifying the expanded form or meaning of abbreviations.
Normative text
Verbatim from WCAG 2.2, W3C Recommendation 12 December 2024. Underlined terms are defined below.
A mechanism for identifying the expanded form or meaning of abbreviations is available.
Definitions used (2)
Glossary definitions are normative. Their notes are informative.
- mechanism
-
process or technique for achieving a result
Informative notes (2)
The mechanism may be explicitly provided in the content, or may be relied upon to be provided by either the platform or by user agents, including assistive technologies.
The mechanism needs to meet all success criteria for the conformance level claimed.
- abbreviation
-
shortened form of a word, phrase, or name where the abbreviation has not become part of the language
initialisms are shortened forms of a name or phrase made from the initial letters of words or syllables contained in that name or phrase
Not defined in all languages.
acronyms are abbreviated forms made from the initial letters or parts of other words (in a name or phrase) which may be pronounced as a word
Informative notes (2)
This includes initialisms and acronyms where:
Some companies have adopted what used to be an initialism as their company name. In these cases, the new name of the company is the letters (for example, Ecma) and the word is no longer considered an abbreviation.
Tier 2 · The gap
Usability & user impact
Where content can meet this criterion and still make things harder for people with disabilities. These are not failures of SC 3.1.4, so raise them as usability defects. Known failures, including failures of related criteria, are listed in Tier 1.
The abbr title attribute alone isn't reliably exposed to keyboard, touch or screen reader users.
Tier 3 · The golden path
Recommended best practice
The pattern that meets the floor, closes the gap, and avoids audit disputes. A recommendation, not a requirement.
Spell out the term on first use followed by the abbreviation, for example "Avoidant/Restrictive Food Intake Disorder (ARFID)".
W3C's Understanding document and techniques for SC 3.1.4 ↗ are informative: sufficient techniques show ways to pass, and documented failures show common ways to fail, but neither changes what the criterion requires.
How SC 3.1.4 maps to the WCAG 3 draft
From this site's reviewed map to the WCAG 3 editor's draft. It's an interpretation: W3C has not published a mapping.
Successor provisions
From WCAG 2.2, section 5.1: “The main content of WCAG 2.2 is normative and defines requirements that impact conformance claims. Introductory material, appendices, sections marked as "non-normative", diagrams, examples, and notes are informative (non-normative). Non-normative material provides advisory information to help interpret the guidelines but does not create requirements that impact a conformance claim.”