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The etymology of the word is disputed. The word first looks like a reference to an 18th-century tool in glassmaking that was developed as a spring pontil.  As stated in the glass dictionary released by the Corning Museum of Glass, a device is a metal rod with a springtime clip that grasps the foot of a vessel therefore avoids the use of a pontil. Gizmos were initially used in the late 18th century.  According to the Oxford English Dictionary, there is anecdotal (not always true) proof for using “gizmo” as a placeholder name for a technical thing whose exact name one can’t remember given that the 1850s; with Robert Brown’s 1886 book Spunyarn and Spindrift, A sailor kid’s log of a trip out as well as home in a China tea-clipper containing the earliest known use in print.