book•mark•let [book-mahrk-let] –noun 1. a bookmarklet is an applet, a small computer application, stored as the URL of a bookmark in a web browser or as a hyperlink on a web page. Whether bookmarklet utilities are stored as bookmarks or hyperlinks, they are designed to add one-click functionality to a browser or web page. 2. a bookmarklet performs some function, one of a wide variety such as a sea