zon·al soil (z??n?l)n. Soil that has well-defined features that are characterized by the weather it is exposed to and the vegetation that grows there.American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.zonal soil n (Physical Geography) soil having a profile determined mainly by the local climate and vegetation. Compare azonal soil, intrazonal soil Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014