<abbr>
An abbreviation or acronym, optionally with its expansion in title.
Baseline: Widely available · Inline text semantics
When to use it
Spell the term out on first use, then abbr for the rest; the title shows on hover and is available to assistive tech.
When not to
Don't rely on title alone to convey essential meaning — touch users never see tooltips.
Key attributes
title- the full expansion
Example
The W3C publishes accessibility guidance.
<p>The <abbr title='World Wide Web Consortium'>W3C</abbr> publishes accessibility guidance.</p>