Definition of thingumbob
: something whose specific name or designation has been forgotten or is not known mysterious electrical thingumbobs that go off with a bang — Literary Review
Start your free trial today and get unlimited access to America's largest dictionary, with:
- More than 250,000 words that aren't in our free dictionary
- Expanded definitions, etymologies, and usage notes
- Advanced search features
- Ad free!
Origin and Etymology of thingumbob
irregular from thingum
First Known Use: 1751
Seen and Heard
What made you want to look up thingumbob? Please tell us where you read or heard it (including the quote, if possible).