A wick is the string or cord that runs through the center of a candle or oil lamp, designed to soak up fuel and burn with a steady flame. When you light a candle, you're actually lighting the wick, which draws up melted wax through tiny spaces in its woven fibers. The wax fuels the flame, which then melts more wax, keeping the cycle going.

Before electric lights, people relied on candles and oil lamps with wicks for light after dark. A properly trimmed wick burns evenly and brightly, while an untrimmed wick creates a smoky, flickering flame. You can still see wicks at work in birthday candles, decorative candles, and old-fashioned lanterns.

The word appears in the phrase to wick away, which means to draw moisture from one place to another, just like a candle wick draws up wax. Athletic shirts are often made from fabrics that wick away sweat from your skin, keeping you dry and comfortable during sports or exercise. The fabric pulls moisture to its outer surface, where it can evaporate, using the same capillary action that makes a candle wick work.