An erect slender annual herb up to 20 cm tall, with slender, cylindrical stems, branches umbellate, the nodes thickened; roots aromatic. Leaves in dense whorls of 4 to 8 at each node, sessile or subsessile, often glaucous; radical leaves 6 to 13 mm long, spathulate or linear - spathulate. Flowers numerous, on stiff filiform pedicels to 1.2 cm long, usually in groups of 3 on long filiform axillary and terminal peduncles; sepals 2.5 mm long, elliptic-oblong, obtuse, with white membranous margins. Fruit (capsule) rounded, equaling the sepals, dehiscing into 3 broadly ovate emarginate valves; seeds numerous smooth, yellowish-brown, without tubercular points.

The herb is cooling, diuretic, febrifuge, relieves thrist, burning sensation of the body, stomachic, aperient, antiseptic and stimulates the heart. Diaphoretic (flowers and tender shoots).