not tractable; difficult to manage or mold; "an intractable disposition"; "intractable pain"; "the most intractable issue of our era"; "intractable metal"
impervious to pleas, persuasion, requests, reason; "he is adamant in his refusal to change his mind"; "Cynthia was inexorable; she would have none of him"- W.Churchill; "an intransigent conservative opposed to every liberal tendency"
existing for a long time; "hopes for a durable peace"; "a long-lasting friendship"
very long lasting; "less durable rocks were gradually worn away to form valleys"; "the perdurable granite of the ancient Appalachian spine of the continent"
serviceable for a long time; "durable denim jeans"
harshly uninviting or formidable in manner or appearance; "a dour, self-sacrificing life"; "a forbidding scowl"; "a grim man loving duty more than humanity"; "undoubtedly the grimmest part of him was his iron claw"- J.M.Barrie
so frightened as to be unable to move; stunned or paralyzed with terror; "petrified with fear"; "she was petrified by the eerie sound"; "too numb with fear to move"
not changeable or subject to change; "a fixed and unchangeable part of the germ plasm"-Ashley Montagu; "the unchangeable seasons"; "one of the unchangeable facts of life"
consisting of great mass; containing a great quantity of matter; "Earth is the most massive of the terrestrial planets"
imposing in size or bulk or solidity; "massive oak doors"; "Moore's massive sculptures"; "the monolithic proportions of Stalinist architecture"; "a monumental scale"
imposing in scale or scope or degree or power; "massive retaliatory power"; "a massive increase in oil prices"; "massive changes"
being the same substance throughout; "massive silver"