Definition of "widget"

A placeholder name for an unnamed, unspecified, or hypothetical manufactured good or product, typically as an example for purposes of explaining concepts.  quotations  examples

A floating device inside a beer can, meant to create foam when opened.  examples

A small scraping tool consisting of a blade and a handle, commonly used to remove paint from glass and other smooth surfaces.  examples

(informal) Synonym of tool, implement, device, gadget, part  examples

(graphical user interface) Any one of the components of a computer application's graphical user interface, such as a Cancel button or text input box that a user interacts with.  examples

(graphical user interface) A small applet that can be placed on the desktop or in a sidebar, etc.  examples