Webster's Revised Unabridged Dictionary · 1913

Zonal

Zonal , adjective

[Latin zonalis.]

Of or pertaining to a zone; having the form of a zone or zones.
Collocations (3)
Zonal equation (Crystallography) , the mathematical relation which belongs to all the planes of a zone, and expresses their common position with reference to the axes.
Zonal structure (Crystallography) , 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 (Biology) , See the Note under Symmetry.