WordNet (r) 3.0 (2006):

widget
    n 1: something unspecified whose name is either forgotten or not
         known; "she eased the ball-shaped doodad back into its
         socket"; "there may be some great new gizmo around the
         corner that you will want to use" [syn: doodad,
         doohickey, doojigger, gimmick, gizmo, gismo,
         gubbins, thingamabob, thingumabob, thingmabob,
         thingamajig, thingumajig, thingmajig, thingummy,
         whatchamacallit, whatchamacallum, whatsis, widget]
    2: a device or control that is very useful for a particular job
       [syn: appliance, contraption, contrivance,
       convenience, gadget, gizmo, gismo, widget]

The Free On-line Dictionary of Computing (19 January 2023):

widget

   1.  A placeholder term used to stand for a real object in
   didactic examples (especially database tutorials).  Legend has it
   that the original widgets were holders for buggy whips.  "But
   suppose the parts list for a widget has 52 entries..."

   2. In a graphical user interface, a combination of a graphic
   symbol and some program code to perform a specific function.
   E.g. a scroll-bar or button. [possibly evoking "window gadget"]
   Windowing systems usually provide widget libraries containing
   commonly used widgets drawn in a certain style and with consistent
   behaviour.

   In Microsoft Windows GUI programming, these are generally known
   as "controls".

   [Jargon File]


The Jargon File (version 4.4.7, 29 Dec 2003):

widget
 n.

    1. A meta-thing. Used to stand for a real object in didactic examples
    (especially database tutorials). Legend has it that the original widgets
    were holders for buggy whips. “But suppose the parts list for a widget has
    52 entries....”

    2. [poss.: evoking ‘window gadget’] A user interface object in X
    graphical user interfaces.