https://doi.org/10.1351/goldbook.N04205
Corrosion is non-uniform if the time average of the corrosion current through a unit area depends on its position on the surface. Non-uniform corrosion can be due to inhomogeneities of structure or of composition of the corroding material, or to inhomogeneities of the environment. Special cases of non-uniform corrosion such as pitting or intergranular corrosion are sometimes called localized corrosion.