Arabhi is a very brisk Raga. It is classified as being the Janya of the 29th Melakarta, Shankarabharanam.
ārohaṇa : S R2 M₁ P D2 Ṡ
avarohaṇa : Ṡ N₃ D2 P M₁ G₃ R2 S

The Nishada and Gandhara are not stressed upon, but used fleetingly and are known as alpa swarams. Though Arabhi technically has SND, SD can also be used beautifully.