goat's beard, in botany: A genus of plants belonging to the class of Syngenesia, and to the order of Polygama aquatilis; and in the natural system ranging under the 49th order, Compositae. The receptacle is naked, the calyx simple, and the pappus plumose. There are 14 species; of which two are British, the pratense and purpureum.

1. The pratense, or yellow goat's beard, has its calyxes equal with the florets, and its leaves entire, long, narrow, leafy, and grassy. In fair weather this plant opens at sunrise, and shuts between nine and ten in the morning. roots are conical and esculent, and are sometimes boiled and served up at table like asparagus. It grows on meadows.

2. The *porrifolium*, or purple goat's beard, has the calyx longer than the radius of the floret; the flowers are large, purple, fingle, and terminal; and the leaves long, pointed, and bluish. The root is long, thick, and esculent. It grows in meadows, and is cultivated in gardens under the name of *salsify*.