di·basic \(ˈ)dī+\adjective Etymology:di- + basic 1.: having two hydrogen atoms capable of replacement by basic atoms or radicals — used of acids (as oxalic or sulfuric acid) 2.: containing two atoms of a univalent metal or their equivalent < dibasic sodium phosphate Na2HPO4 > 3.: having two basic hydroxyl groups : able to react with two molecules of a monobasic acid — used of bases and basic salts • di·basicity\(|)dī+\noun-es