Webster's Revised Unabridged Dictionary · 1913

Meadowsweet

Meadowsweet , noun

(Botany) The name of several plants of the genus Spiraea, especially the white- or pink-flowered Spiraea salicifolia, a low European and American shrub, and the herbaceous Spiraea Ulmaria, which has fragrant white flowers in compound cymes.

Also: Meadowwort