A mining method where miners dig trenches or shafts perpendicular to a coal seam or ore vein to follow and extract the valuable material.
From English dialect, possibly from 'costean' meaning a mining prospecting trench. A technical mining term dating to the Middle Ages when mineral extraction began to require systematic methods.
Costeaning is why abandoned mines have those perpendicular trenches cut into hillsides—miners were literally following veins of ore underground, creating a staircase of trenches as they worked deeper.
Complete word intelligence in one call. Free tier — 50 lookups/day.