the quality of being difficult to do; "he assigned a series of problems of increasing hardness"; "the ruggedness of his exams caused half the class to fail"
the property of being rigid and resistant to pressure; not easily scratched; measured on Mohs scale
the work of making something smooth and shiny by rubbing or waxing it; "the shining of shoes provided a meager living"; "rbry Dunday he gave his car a good polishing"
marked by exceptional merit; "had shining virtues and few faults"; "a shining example"