sweet flag
noun
1.
a plant,
Acorus calamus,
of the arum family, having long, sword-shaped leaves and a pungent, aromatic rootstock.
Also called
sweet calamus
.
Origin
1775-85
British Dictionary definitions for
sweet flag
sweet flag
noun
1.
an aroid marsh plant,
Acorus calamus,
having swordlike leaves, small greenish flowers, and aromatic roots
Also called
calamus
Word Origin
C18: see
flag
²