solid

accurate admirable analytical analytic/analytical block blocky careful close cogent compact concrete concrete convincing credible denser dense determined fat fatter firmly firm firm fixed fine good good hard-bitten hard harder hardy heartiest hearty heavyset homogeneous hulking immovable impenetrable impregnable incompressible learned lump marvelous massive monolithic more careful more concrete more concrete more compact more analytic more accurate more analytical more analytical more credible more telling more rigid more valid more practical more proper more trustworthy most analytic most analytical most analytical most trustworthy most telling neck and neck old palpable physical practical proper puissant realest real remarkable reliable rigid ripping rocky rocky rotund round satisfactory secure secure set solvent sound sound sound stable stalwart steady stiff stocky straight strong substantial substantial substantial superb sure surest tactual tactile tangible telling tenacious thickset thick thick thick tight tighter tightest tough toughest tougher trustier trustworthy/trusty trustiest unanimous unbreakable unbroken undivided unfailing unmovable unwavering unyielding valid veridical well-made well-founded whole