This is not about inserting tool tips with shortcodes, this is about adding meanings to some words on your website which will automatically appear on hovering the mouse pointer over the predefined words in WordPress. Text Hover, a WordPress plugin lets you add hover text to regular words. The plugin provides you a handy way for providing explanations of names, terms, phrases, and acronyms mentioned inside your posts, pages and comments.
Install and activate Text Hover plugin then visit Dashboard -> Settings -> Text Hover page and type your words with their definitions/meaning in this style:
WP => WordPress
BP => BuddyPress
PHP => Hypertext Pre-processor
DB => Database
and so on…
Scroll a little bit down and there are more options like you can make your words case-sensitive, you can enable them on comments too, you can set text hover to show up only once per term per post etc.
When you’re done adding your words, save your settings, visit the frontend of your website and test it by hovering the mouse pointer over the words you have defined. It doesn’t changes any color, size or style of the words. All words looks same, it just shows up the tooltips on text hover.