GNU Collaborative International Dictionary of English

Found one definition

1.       
   Calamus , n.; pl. Calami . [L., a reed. See Halm.]
   (Bot.) The indian cane, a plant of the Palm family. It furnishes the common rattan. See Rattan, and Dragon's blood.
   1913 Webster
   (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.
   1913 Webster
   (Zool.) The horny basal portion of a feather; the barrel or quill.
   1913 Webster