prosˌenneaˈhedral, a. Cryst. rare.
[f. F. prosenneaèdre (Haüy) (f. Gr. πρός approaching to + enneaèdre) + -al1, after enneahedral.]
(See quot.) Also prosenneˈëdrous a. rare—0.
| 1805–17 R. Jameson Char. Min. (ed. 3) 208 Prosenneahedral,..having nine faces on two adjacent parts, as in the prosenneahedral tourmaline..; in which the prism has nine sides, and one of the extremities nine planes, and the other only three. 1858 Mayne Expos. Lex., Prosenneædrus, Min., having nine faces upon two adjacent parts. Applied by Haüy to a variety of tourmaline..: prosenneëdrous. |