pennyroyal

noun2

1. •
   Mentha pulegium, a plant of the mint family, formerly much used in various medicinal treatments and as a flea repellent.

   • Dioscorides says that Pennyroyal makes thin, tough phlegm, warms the coldness of any part whereto it is applied, and digests raw or corrupt matter. — 1653
2. •
   (no longer used) A traditional old well-known song, especially a spiritual folksong.

   • Offenbach and the old college airs, song and dance tunes and pennyroyals, formed the staples for the introduction of hits on manners and times. — 1878