tropal, a. Geom.
(ˈtrəʊpəl)
[f. L. trop-us trope n. + -al1.]
Pertaining to or constituting a trope: see trope n. 8.
| 1875 Cayley Math. Papers IX. 519 The quartic surface has also four tropes (planes which touch the surface along a conic)... The conic of contact or tropal conic in each plan being the intersection of the plane with the before-mentioned quadric surface. Ibid. 520 Ordinary tropal planes each touching the surface in a proper conic. |