[{"Bold_text": "adjective", "List Items": ["hard or impossible to manage; stubbornly disobedient:a refractory child.Synonyms: ungovernable , recalcitrant , disobedient , intractable , headstrong , mulish , perverse , obstinate Antonyms: tractable , obedient", "resisting ordinary methods of treatment.", "difficult to fuse, reduce, or work, as an ore or metal."]}, {"Bold_text": "noun", "List Items": ["a material having the ability to retain its physical shape and chemical identity when subjected to high temperatures.", "refractories,bricks of various shapes used in lining furnaces."]}]