noun, plural giz·mos.
noun, plural gis·mos. Informal.
- a gadget or device: What is this gismo supposed to do?
noun plural -mos
- slang a device; gadget
1942, “Marine and Navy usage for any old thing you can’t put a name to” [“Life” magazine, July 30, 1945], of unknown origin, perhaps a made-up word.