from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A monoterpenoid ketone, found in pennyroyal, that is toxic to dogs and cats
from The Century Dictionary and Cyclopedia
- n. An oily unsaturated ketone related to the terpenes, , found in the oils of Spanish and American pennyroyal (Mentha Pulegium and Hedeoma pulegioides), etc. It has an odor resembling peppermint.
Sorry, no etymologies found.
Its concentration increases with the age of the leaf, so older leaves taste more cooling; hot and dry growing conditions cause menthol to be transformed into a noncooling, somewhat harsh by-product pulegone, the characteristic volatile in pennyroyal.