| Doorstone (n.) The stone forming a threshold. Thesaurus Entries base, basement, basis, bearing wall, bed, bedding, bedrock, doorsill, doorstone, floor, flooring, fond, footing, foundation, fundament, fundamental, ground, grounds, groundsel, groundwork, hardpan, mudsill, pavement, principle, radical, riprap, rock bottom, rudiment, seat, solid ground, solid rock, stereobate, stylobate, substratum, substruction, substructure, terra firma, threshold, underbuilding, undercarriage, undergirding, underpinning, understruction, understructure, window sill | ![]() |