Mining. north. [Possibly a variant of SQUAD sb.2, loose tin or other ore mixed with earth (Cornwall).] A layer of stone or worthless coal at the bottom of a seam.
1860. Eng. & For. Mining Gloss., Newcastle Terms (ed. 2), 65.
1865. Our Coal & Coal-pits, 51. A black substance, called swad, resembling soot caked together.
