I’ve had too many conversations about this, causing too much friction, so I’m going to set down my thoughts here to clarify my position on “a11y”.
The abbreviation a11y is a numeronym, in which the letters between the first and last letters of a word are replaced by a number indicating how many letters are replaced.
There are eleven letters between the initial a and final y of accessibility, so its numeronym is a11y.
Other examples of numeronyms are i18n for internationalisation and l10n for localisation. They are convenient when writing because they mean you don’t have to write a long word out in full.
Numeronyms are written conventions not intended to be verbalised in their abbreviated form.
In the case of i18n and l10n, this is not even possible.
However, when the a11y numeronym is written, and especially when typed in certain fonts, the eleven looks like a double lower case letter L, tempting people to say it out loud as “alley”.
In most contexts, this makes no sense and only causes confusion. If you were to say to a front-end developer, “I hope you’re taking alley into account”, they are unlikely to know that you mean “I hope you’re taking accessibility into account”.
This principle also applies to many other types of abbreviation. For example, “etc” is verbalised as “et cetera”, something we do without even thinking about it.
There are examples where abbreviations have become the accepted form of pronunciation, such as the acronyms scuba for self-contained underwater breathing apparatus and radar for radio detection and ranging. They don’t even have to be capitalised.
There also initialisms, where a phrase is written as its initials and verbalised by saying the initials out loud, such as FBI for Federal Bureau of Investigations. These should remain capitalised (dots are optional).
There are also words that work on the reverse principle where saying the abbreviation out loud mimics the way it’s spelled in full, such as writing K9 for canine.
Critically, none of these acronyms, initialisms, and abbreviations resemble any other existing words when spoken.
That is not the case with a11y. When a11y is spoken as if the eleven is a double L, it inevitably sounds like alley (as in a roadway) or ally (as in a friend).
That’s unhelpful and only causes confusion.
Some people try to say a11y as a-eleven-y, which is even more confusing, if you don’t know about numeronyms.
Just say accessibility. Yes, this is an awkward – perhaps even an inaccessible – word, but it’s what we have, at least until someone comes up with a better one.
It doesn’t seem to be any better in languages other than English: accessibilidad (Spanish), accessibilité (French), toegankelijkheid (Dutch), tillgänglighet (Swedish).
There are, of courses, exceptions (there are always exceptions).
When a11y is a proper noun used as part of a phrase denoting a product or event, it’s entirely reasonable to pronounce it as alley because it’s in context.
A good example is the Australian digital accessibility conference A11y Camp. By making it a proper noun and part of a compound phrase, saying it as Alley Camp makes sense and is convenient. Same goes for the A11y Collective.
None of this is an argument against using a11y as a written abbreviation. I’ve been taken to task for suggesting that using the numeronym is lazy.
This criticism presupposes that laziness is inherently bad, which is not an opinion I hold.
Lazy loading (only loading digital resources when they’re needed), lazy coding (such as setting a CSS property to one variable instead of four when all the variables are the same), and lazy evaluation (deferring work until necessary) are all ways of providing convenience and strategic optimisation.
In the same way, writing a11y is strategically lazy, convenient and efficient.
The only reason any of this is an issue is because a11y happens to look like it can be pronounced.
Just because it can, doesn’t mean it should.
For clarity and common sense, I recommend using a11y as a written abbreviation and saying it out loud as accessibility.
But you do you. If you want to pronounce a11y as alley and it makes sense to whoever you’re talking to, go right ahead.