1. (n.) One who, or that which, underlays or is underlaid; a lower layer.
2. (n.) A perpendicular shaft sunk to cut the lode at any required depth.
Thesaurus Entries
band, bed, bedding, bedrock, belly, belt, bottom, bottom side, breech, buttocks, couche, course, deck, downside, floor, fundament, gallery, hardpan, layer, ledge, level, lower side, lowest layer, lowest level, measures, nether side, nethermost level, overlayer, overstory, rock bottom, seam, shelf, stage, step, story, stratum, substratum, superstratum, thickness, tier, topsoil, underbelly, underneath, underside, understory, understratum, zone
