a scientific name of a remarkableAustralian genus of passerine birds, the spine-tails. It longremained of uncertain position . . . and finally it was madethe type of a family, Orthonycidae. In the typespecies, O. spinacauda . . . the shafts of thetail-feathers are prolonged beyond the legs. (`Century.')Thename is from the Greek 'orthos, straight, and 'onux, a claw. See Log-Runner and Pheasant's Mother.