[mass noun] Cinchona bark.
- ‘For example, herbalists claimed that Peruvian bark cured malaria.’
- ‘He also advocated that specific remedies could be applied to each such disease, his favourite example being the prescription of Peruvian bark for intermittent fever or ague.’
- ‘Ague was known to be related to mosquito bites, and was treated with Peruvian bark.’
- ‘Add a little nutmeg, some powdered reindeer horn, five vine leaves and a piece of Peruvian bark.’