sweet flag

a plant, Acorus calamus, of the arum family, having long, sword-shaped leaves and a pungent, aromatic rootstock.

Also called sweet calamus.

Origin of sweet flag

First recorded in 1775–85

Its home is a hole in the ground, and boys often amuse themselves by running pieces of sweet-flag in the hole.

Harper's Young People, August 31, 1880 |Various
However, as the leaves of the Sweet-Flag are fragrant, the odor will be a means of recognizing it.

Ginseng and Other Medicinal Plants |A. R. (Arthur Robert) Harding
It trembles in the air, the sprig of sweet-flag, and smiles its dry green smile.

The Old House and Other Tales |Feodor Sologub
Sweet-Flag is employed as an aromatic stimulant and tonic in feeble digestion.

Ginseng and Other Medicinal Plants |A. R. (Arthur Robert) Harding

He is as genuine, as wholesome and real as sweet-flag and clover.

The Atlantic Monthly, Volume 13, No. 77, March, 1864 |Various

sweet flag

an aroid marsh plant, Acorus calamus, having swordlike leaves, small greenish flowers, and aromatic roots Also called: calamus

C18: see flag ²