n. (Math.) In the quaternion analysis, a quantity that has magnitude, but not direction; -- distinguished from a vector, which has both magnitude and direction. [ 1913 Webster ]

‖n. [ L., flight of steps. ] (Zool.) Any one of numerous species of marine gastropods of the genus Scalaria, or family Scalaridae, having elongated spiral turreted shells, with rounded whorls, usually crossed by ribs or varices. The color is generally white or pale. Called also ladder shell, and wentletrap. See Ptenoglossa, and Wentletrap. [ 1913 Webster ]

a. [ L. scalare, scalaria, staircase, ladder + -form: cf. F. scalariforme. ] 1. Resembling a ladder in form or appearance; having transverse bars or markings like the rounds of a ladder; as, the scalariform cells and scalariform pits in some plants. [ 1913 Webster ]

2. (Zool.) Like or pertaining to a scalaria. [ 1913 Webster ]

a. [ L. scalaris, fr. scalae, pl. scala, staircase, ladder. ] Resembling a ladder; formed with steps. [ Obs. ] Sir T. Browne. [ 1913 Webster ]