Wikipedia - Wiktionary

Yahoo's desktop widgets project was shut down in 2012, but there are still interesting and handy widget applications out there that can offer you easy access to information or to frequently used programs. Such a tool is Wikipedia – Wiktionary, a lightweight utility designed to provide you with a faster method for searching the well-known online encyclopedia.
In order to use it, the Yahoo! Widget Engine must already be installed on your computer. Once you do that, Wikipedia – Wiktionary can be integrated into the dedicated HUD (heads-up display) of the engine, allowing you to access it from there.
The widget displays the Wikipedia logo, together with a search box, where you can write anything. Pressing the 'Enter' key opens the corresponding page in your default web browser, enabling you to view the search results. Besides Wikipedia, you can search the Wiktionary (online dictionary), Wikiquote, Wikibooks, Wikisource and Wikinews, all in multiple languages.
Right-clicking on the interface opens a menu that you can use to hide the widget or access the 'Preferences' section. Here, users can adjust the size of the widget, modify its transparency and set the program to automatically clear the input word when pressing 'Enter'.
Optionally, the widget can be set to stay on top of or below all the other opened windows, as well as ignore all the mouse events or prevent dragging. Choosing one of the last two options implies that you can still interact with the widget, but only in 'Heads Up Display' mode.
Although Wikipedia – Wiktionary is just a simple widget, it offers you an easier way of searching any of the Wiki online services, directly from your desktop.