The American Heritage® Dictionary of the English Language, 4th Edition
n. The pathological formation of patches of gum on certain plants, such as sugar cane and some fruit trees, resulting from attack by insects, microorganisms, or adverse weather conditions.
n. The formation of patches of a gummy substance on the surface of certain plants, particularly fruit trees, caused by sap oozing from wounds or cankers.
The Century Dictionary and Cyclopedia
n. In botany, the formation of gum in the older organs of plants by the transformation of large groups of tissue, as in the production of cherry-gum and gum tragacanth.
n. An abnormal production and flow of gum from cracks or wounds of trees.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. pathological production of gummy exudates in citrus and various stone-fruit trees
n. disease of citrus trees caused by the fungus Phytophthora citrophthora
Word Usage
"Symptoms of sunscald closely mimic the gummosis disease, but are restricted to the side of the trunk facing the sun."