Zonal
Pronunciation : Zon"al
Part of Speech : a.
Etymology : [L. zonalis.]
Definition : Defn: Of or pertaining to a zone; having the form of a zone or zones. 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.
Source : Webster's Unabridged Dictionary, 1913