[pen-ee-roi-uh
l] 
| 1. | an aromatic Old World plant, Mentha pulegium, of the mint family, having clusters of small purple flowers and yielding a pungent essential oil used medicinally and as an insect repellent. |
| 2. | Also called mock pennyroyal. a similar, related plant, Hedeoma pulegioides, of eastern North America, having bluish flowers growing from the leaf axils. |
| 3. | any of several other aromatic plants of the mint family. |