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

Chris

This WordPress plugin will allow users to maintain a list of acronyms and abbreviations which can be managed in the WordPress Dashbard. These acronyms will be automatically wrapped in the appropriate HTML markup when found in posts, pages and comments.
The plugin will auto-detect whether the currently active theme uses HTML5, and will output the appropriate HTML acronym or abbreviation element, e.g. <code><acronym title="Hypertext Markup Language">HTML</acronym></code> (or <code><abbr title="Hypertext Markup Language">HTML</abbr></code> for HTML5).
Based on Joel Pan’s excellent Acronyms, which is no longer being actively maintained. The onset of HTML5 and the deprecation of <code><acronym></code> in favour of <code><abbr></code> led me to fork Joel’s plugin and create Acronyms 2.

Acronyms 2

A plugin to automatically mark up known acronyms and abbreviations in posts and comments. Allows users to manage lists of acronyms through the WordPre …

Abbreviations for WordPress vs Acronyms 2