Definition(s)
Pitting
Localized corrosion of a metal surface in a small area and takes the form of cavities called pits. Pitting can be highly localized (including a single pit) or wide spread on a metal surface.
Source: API 570, Piping Inspection Code: In-service Inspection, Rating, Repair, and Alteration of Piping Systems, Fourth Edition, February 2016, with Addendum May 2017. Global Standards