derive

base, basement; plinth, dado, wainscot; baseboard, mopboard; bedrock, hardpan [U.S.]; foundation (support); substructure, substratum, ground, earth, pavement, floor, paving, flag, carped, ground floor, deck; footing, ground work, basis; hold, bilge., bottom, nadir, foot, sole, toe, hoof, keel, root; centerboard.