You want to put a short text on your pages when you move the mouse over a link that sends to another article on the website?
If you want to add a hover text (also called tooltip) on your WordPress pages, like Wikipedia do, there are a lot of plugins that can save you time :
This plugin allows you to easily define help text that appears when a visitor hovers their mouse over a word or phrase in a post or page.
CM Tooltip Glossary
Easily create a glossary, encyclopedia or dictionary of your terms and show responsive tooltips when users hover over the terms.
Glossaries are a valuable option for most websites: they provide a brighter and more profitable reading experience to the user and can significantly improve your website’s SEO and ranking.
WP Glossary Hover
WP Glossary Hover adds helpful tooltips to user defined glossary terms. Terms are highlighted and when hovered over shows the term definition.