Achyranthes aspera (common names: chaff-flower,[1] prickly chaff flower,[2] devil's horsewhip,[3] Sanskrit: अपामार्ग apāmārga) is a species of plant in the family Amaranthaceae.

[6] The juice of this plant is a potent ingredient for a mixture of wall plaster, according to the Samarāṅgaṇa Sūtradhāra, which is a Sanskrit treatise dealing with Śilpaśāstra (Hindu precepts of art and construction).

The flowering spikes, rubbed with a little sugar, are made into pills, and given internally to people bitten by mad dogs.

The leaves, taken fresh and reduced to a pulp, are considered a good remedy when applied externally to the bites of scorpions.

Ecdysterone, an insect moulting hormone, and long chain alcohols are also found in Achyranthes aspera.