1. Also called althea. a widely cultivated shrub or small tree, Hibiscus syriacus, of the mallow family, having showy white, reddish or purplish flowers.
2. Also called Aaron's-beard. a St.-John's-wort, Hypericum calycinum, having evergreen foliage and showy yellow flowers.
3. a plant mentioned in the Bible. Song of Solomon 2:1.