If you're dextrous, you're graceful and skilled. A dextrous magician can wave her hands around and appear to pull a rabbit out of thin air.
When you're dextrous, you have a physical skill — you could be a dextrous football player or a dextrous bass guitarist. You can also describe someone as dextrous who's a quick or clever thinker: "Her jokes are hilarious because she's really verbally dextrous." You can also spell this word as dexterous, and both versions have a Latin root, dexter, "skillful."