Jauntiness is a characteristic of being happy, carefree, and confident. Your jauntiness makes you a positive and fun person to be around.
When you see your friend hurrying toward you, the jauntiness in her step may tell you she got some good news she was waiting for. Even clothes and music can express jauntiness, if they're bright and cheerful. This word comes from the adjective jaunty, which originally meant "elegant or stylish," from an Anglicized and slightly mispronounced version of the French gentil, "nice or pleasing."