Definition of "electrolytic"

However, approaching energisation, electrolytic corrosion was discovered between the copper contact wire and aluminium beams in the tunnel. The corrosion was caused by the dissimilar metals. An aluminium contact wire system which prevents electrolytic corrosion was subsequently developed, tested and adopted within a year, and replaced the earlier copper installation.

2020 July 1, “First electric trains operate through Severn Tunnel”, in Rail, page 20