Other forms: shiniest; shinier; shinily
Shiny describes something with a smooth, glossy surface. If you want to see your reflection in the glass table, you'll have to polish it to keep it shiny.
Something shiny has a shine, a brightness that comes from reflecting light. Are you into shiny new cars, or shiny diamonds? Or do you like shiny, happy people? Good synonyms are lustrous, sheeny and glossy.