MrXHellboy

Wrap abbreviations for search engine optimization and support other applications
Using abbreviations on your website is not a bad idea since people will get tired of reading the same over and over again. 
Unfortunately, search engines and other application which might render your website are not that great with abbreviations. 
Reading software, spelling checkers, language translations or other applications might fall over them.
By wrapping abbreviations in the therefor “abbr” HTML element, along with a title(description), applications relying on the structure of your site, can do their job just fine.
Search engines will read the abbreviation and the description which increases the chance for more relevance by specific terms used on search engines like Google.
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Abbreviations for WordPress

Wrap abbreviations for search engine optimization and support other applications

Whodunit

Jb Audras

This plugin should be used to supply abbreviation support in the TinyMCE visual editor. Once activated, it provides an “ABR” button which allows editor to indicate the meaning of each abbreviation used in Pages, Posts or any custom post types used in your WordPress installation. The markup is fully compatible with accessibility rules like Web Content Accessibility Guidelines (WCAG). It uses <code><abbr>…</abbr></code> HTML markup instead of the deprecated <code><acronym>…</acronym></code> HTML markup.
Available languages
<ul>
<li>English</li>
<li>French</li>
</ul>
You can add your own language pack: contribute <a href="https://translate.wordpress.org/" rel="nofollow ugc">here</a>! Contributors will be linked back here. 
Search Plugins > Abbreviation button for tinymce and add your translations. Many strings are commented to help you to understand context.
Credits
<a href="https://jeanbaptisteaudras.com/" title="Jean-Baptiste Audras" rel="nofollow ugc">Jean-Baptiste Audras</a>, WordPress projects manager at <a href="http://www.whodunit.fr/" title="Whodunit Web Agency" rel="nofollow ugc">Whodunit</a> and WordPress developer. @audrasjb on <a href="https://twitter.com/audrasjb" title="@audrasjb on Twitter" rel="nofollow ugc">Twitter</a> or <a href="https://github.com/audrasjb" title="@audrasjb on Github" rel="nofollow ugc">Github</a>.

Abbreviation button for TinyMCE

Provides abbreviation button for WordPress TinyMCE visual editor.

Abbreviations for WordPress vs Abbreviation button for TinyMCE