'Zonal equation' definitions:

Definition of 'Zonal equation'

From: GCIDE
  • Zonal \Zon"al\, a. [L. zonalis.] Of or pertaining to a zone; having the form of a zone or zones. [1913 Webster]
  • Zonal equation (Crystallog.), the mathematical relation which belongs to all the planes of a zone, and expresses their common position with reference to the axes.
  • Zonal structure (Crystallog.), a structure characterized by the arrangements of color, inclusions, etc., of a crystal in parallel or concentric layers, which usually follow the outline of the crystal, and mark the changes that have taken place during its growth.
  • Zonal symmetry. (Biol.) See the Note under Symmetry. [1913 Webster]