The Ferruginous Hawk (ferruginous = from Latin ferrum – iron, ferrgin-, iron rust, iron-rust color – reddish-brown), Buteo regalis (Latin, royal hawk), is a large bird of prey and belongs to the broad-winged buteo hawks. An old colloquial name is "Ferrugineous Rough-leg", due to its similarity to the closely related Rough-legged Hawk (B. lagopus).