Widget
In Fat Client universe, typically a GUI-object supported by a library/FrameWork.
In Rich Client/Thin Client universe, it typically refers to a small area within a page (like a Portlet) that's generated just by calling a chunk of JavaScript, which might be executed on an entirely separate WebSite (ThirdPartyJavaScript).
http://en.wikipedia.org/wiki/Web_widget
Twitter https://business.twitter.com/optimize/resources/
Edited: | Tweet this! | Search Twitter for discussion