diametral
Di*am"e*tral, a. Etym: [Gr. F. diamétral.] Defn: Pertaining to a diameter; diametrical. Diametral curve, Diametral surface (Geom.), any line or surface which bisects a system of parallel chords drawn in a curve or surface. -- Diametral planes (Crystal.), planes in which two of the axes lie. Di*am"e*tral, n. Defn: A diameter. [Obs.] Sir T. Browne.