Synonyms to underlayer

fundament, backside, base, basement, basis, beam, bearing wall, bed, bedding, bedrock, behind, belly, bottom, bottom side, breech, buttocks, derriere, downside, floor, flooring, fond, footing, foundation, fundamental, ground, grounds, groundwork, hardpan, lower side, lowest layer, lowest level, nether side, nethermost level, pavement, posterior, principle, radical, rear, riprap, rock bottom, rudiment, rump, seat, sill, solid ground, solid rock, stereobate, stylobate, substratum, substruction, substructure, terra firma, underbelly, underbuilding, undercarriage, undergirding, underneath, underpinning, underside, understruction, understructure, band, Ace bandage, Band-Aid, Bund, German band, Mystik tape, Philharmonic, Rochdale cooperative, Scotch tape, accouple, accumulate, act in concert, act together, adhesive tape, affiliate, age group, agglutinate, alliance, ally, amalgamate, amass, amateur band, anklet, application, armlet, articulate, assemblage, assemble, assembly, associate, association, axis, band together, bandage, bandaging, bandeau, bar, battalion, batten, be in league, begird