prismoidal, a.
(prɪzˈmɔɪdəl)
[f. prec. + -al1.]
Of the form of, or pertaining to, a prismoid.
prismoidal formula, a formula for the measurement of railway cuttings or the like, based on the consideration of a solid body as being composed of prismoids. prismoidal railway, a railway in which the wheels run on a single central prism-shaped rail mounted on posts; a mono-railway.
| 1826 Kirby & Sp. Entomol. IV. xlvi. 266 Prismoidal.., having more than four sides and whose horizontal section is a polygon. 1872 E. Morris (title) Easy Rules for the Measurement of Earthworks by means of Prismoidal Formulæ. 1874 P. Smyth Our Inher. ii. 16 After chipping off the prismoidal angles and edges. 1884 Knight Dict. Mech., Suppl., Prismoidal Railway, a wooden or iron beam is supported on posts, the cars are mounted saddle-fashion; the engine grips the rail. Used in South Africa. |