What is "sweet flag"

Calamus \Cal"a*mus\, n.; pl. Calami. [L., a reed. See Halm.]

1. (Bot.) The indian cane, a plant of the Palm family. It furnishes the common rattan. See Rattan, and Dragon's blood.

2. (Bot.) A species of Acorus ( Acorus calamus), commonly called calamus, or sweet flag. The root has a pungent, aromatic taste, and is used in medicine as a stomachic; the leaves have an aromatic odor, and were formerly used instead of rushes to strew on floors.

3. (Zo["o]l.) The horny basal portion of a feather; the barrel or quill. [1913 Webster] ||

n. a perennial wetland plant, ''Acorus calamus'', with an aromatic medicinal root, formerly used to strew floors, also known as calamus

n. perennial marsh plant having swordlike leaves and aromatic roots [syn: calamus, sweet calamus, myrtle flag, flagroot, Acorus calamus]

Sweet flag can refer to several species of the genus Acorus and Iris:

• Acorus americanus, American sweet flag
• Acorus calamus, common sweet flag
• Acorus gramineus, Japanese sweet flag or grassy-leaved sweet flag
• Iris pallida, also called sweet iris
• Iris pseudacorus, also called yellow flag