Refined means made pure or improved by removing unwanted parts. When crude oil gets refined into gasoline, impurities and extra substances are filtered out until what remains burns cleanly in car engines. When sugar cane gets refined into white sugar, workers process it to remove molasses and other materials, leaving behind pure white crystals.

The word also describes people with excellent manners, taste, and education. A refined person might know which fork to use at a fancy dinner, appreciate classical music, or speak thoughtfully and politely. Someone with refined tastes might prefer well-crafted furniture over cheap plastic items, or choose books carefully rather than reading whatever's most popular.

Refined can describe anything improved through careful attention: a writer refines her essay by removing unnecessary words and sharpening her arguments. A pianist refines his technique through years of practice. The word suggests polish and sophistication, whether you're talking about materials, manners, or skills.

The opposite of refined is crude or rough. Crude oil is unrefined. Rough manners are unrefined. When you refine something, whether it's sugar, your soccer skills, or your science project, you're making it better by removing flaws and impurities until what remains is cleaner, clearer, or more effective.