Copper-bottomed
Suggest a CorrectionMeaning
Completely reliable, secure or trustworthy; unlikely to fail under pressure. Informal but common in business and political language. It may describe reliability even when success is not literally guaranteed. Regional use: British English.
Origin
The Royal Navy began experimenting with copper sheathing in 1761 to protect wooden hulls from marine growth and shipworm and to preserve sailing performance. Well-found vessels were advertised as copper-bottomed in the late 18th century. The technical mark of an expensive, durable hull then broadened into the British figurative sense of a dependable plan, guarantee or reputation.
Research Sources
Variants
- Copper-bottomed guarantee
- Copper-bottomed certainty
Usage Examples
- The lender wanted a copper-bottomed guarantee before releasing the funds.
- No forecast is copper-bottomed, however impressive the chart looks.
- Her reputation for fair weights was copper-bottomed after thirty years in the market.