Category:Zonal

Zon"al, a. Etym: [l. zonalis.]

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.