Corrode/kəˈrəʊd/ Definition 1 of 2Pro Tip 1/3Not Instant Corrode suggests a slow process, not something that happens quickly. The old bridge corroded over decades of exposure. Pro Tip 2/3Physical Change Use 'corrode' to describe the physical damage of materials, usually by chemicals or weather. Acid rain can corrode building surfaces. Pro Tip 3/3Visible Effects Corrosion often results in noticeable changes like rust or color fading. The pipes corroded and turned a greenish color.