Glossary · Accessibility term
a11y
a11y is shorthand for the word accessibility, and it means that and nothing narrower. The number is a letter count. Take accessibility, keep the a and the y, and replace the 11 letters in between with the number. That trick has a name, numeronym, and you will meet its siblings all over software. i18n for internationalization, l10n for localization, k8s for Kubernetes. Out loud you will most often hear "ally", which is worth knowing before you sit in a meeting and try to pronounce it off the page.
In practice
You will meet it in job titles, where somebody is an a11y engineer. In channel names, hashtags and package names too. It is a practitioner's shorthand rather than a defined term. That difference matters the moment you read it in a procurement document or an audit report. Nobody has ever fixed its scope the way the standard fixes the scope of its own vocabulary.
The standards do not use it. WCAG spells accessibility out in full, and so do the ARIA specification and the name computation, and none of the three defines a11y as a term. So a document using it is somebody writing in the field's own dialect rather than quoting anything, which is useful to know before you treat the word as though it carried a definition.
Do not use it with customers. A line reading "our a11y commitment" tells a reader who has never met the word nothing at all, which rather defeats the purpose of writing it down. Inside a team it saves keystrokes. On a public page it only gatekeeps.
Why it matters
Knowing the abbreviation lets you follow the conversation. Nearly every practitioner community, testing tool and open-source project in this field uses it, so the word is the door into the material rather than a wall in front of it. That is this entry's whole job. Read it once, and every hashtag and package name that used to look like a typo starts reading as English.
How to say it
Out loud it is usually "ally", the same as the English word. You will also hear A-eleven-Y, or A-one-one-Y. The homophone is a happy accident rather than the reason anybody coined the thing, and our research turned up no reliable record of who first did or when.
Where this shows up on the site
Related terms
Knowing the word is the easy part.
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