Brighten

A room feels dark and sad. The curtains are heavy, and the lamps are off. Then, someone opens the curtains wide and turns on a soft, warm light. The grey walls suddenly look cream, the dull floor seems golden, and the whole space feels alive again. The person did not change the furniture or paint the walls. They simply brought in light. What did the person do to the room? They brightened it (made it shine).

Brighten means to make something lighter or more illuminated, or to make a situation more cheerful. Shine, by contrast, means to emit light, not to add light to something else. So, brighten focuses on the act of adding light or cheer to something that was dull or dark. Shine focuses on the source of light itself. In other words, a lamp makes the room shine with its light; While the room is brightened by turning on the lamp.