Arnica /ˈɑːrnɪkə/ is a genus of perennial, herbaceous plants in the sunflower family (Asteraceae).

The genus name Arnica may be derived from the Greek arni, "lamb", in reference to the plants' soft, hairy leaves.

Arnica was previously classified in the tribe Senecioneae because it has a flower or pappus of fine bristles.

[3] The seedlike fruit has a pappus of plumose, white or pale tan bristles.

[3] The species Arnica montana, native to Europe, has long been used in folk medicine, but there is no clinical evidence for its use as an effective therapy.