Definition of plagihedral in English:

plagihedral

adjective

rare
  • Having or designating certain symmetrical crystal faces whose axes are each at the same oblique angle to the vertical, occurring especially in quartz, where the orientation of these faces indicates whether the crystal is laevorotatory or dextrorotatory.

Origin

Early 19th century; earliest use found in Robert Jameson (1774–1854), geologist and natural historian. From ancient Greek πλάγιος oblique, slanting + -hedral, after French plagièdre (R. J. Haüy 1797, in Jrnl. des Mines 28255).

Pronunciation

plagihedral

/ˌpleɪdʒɪˈhiːdr(ə)l/