A vocabulary of landscape — a landscape of words 1068 entries

dyke

DYKE
A dry-stone wall built without mortar — each stone fitted by hand, held by gravity and the skill of the builder. In Scotland, dykes divide fields, mark boundaries, and provide shelter from the wind. Also a geological term: a sheet of igneous rock that cuts across existing strata.
Etymology
Scots and Northern English, from Old English dīc (ditch, embankment). The geological sense dates to the 18th century.