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perennial Old World herb having rayed flower heads with blue florets cultivated for its root and its heads of crisp edible leaves used in salads

perennial Old World herb having rayed flower heads with blue florets cultivated for its root and its heads of crisp edible leaves used in salads

A thick-rooted perennial (Cichorium intybus) native to Europe but widely grown for its young leaves used as salad greens and for its roots, dried and ground-roasted, used to flavor or adulterate coffee. (From Webster, 3d ed)

It is bitter, and was once given as a tonic. The root, roasted and ground, is often used instead of, or mixed with, coffee.