<p><strong>Verb</strong></p><ul><li>To become lighter or less dark; brighten: The sky lightened after the storm.</li><li>To brighten or light up, as the eyes or features: Her face lightened when she heard the good news.</li><li>To flash as or like lightning (often used impersonally with it as subject): It thundered and lightened for hours.</li><li>Archaic: To shine, gleam, or be bright: steel blades lightening in the sun.</li></ul><p><strong>Noun</strong></p><ul><li>To give light to; illuminate: A full moon lightened the road.</li><li>To brighten (the eyes, features, etc.): A large smile lightened his face.</li><li>To make lighter or less dark: Add white to lighten the paint.</li><li>Obsolete: Enlighten.</li><li>Obsolete: To flash or emit like lightning (usually followed by out, forth, or down): eyes that lightened forth implacable hatred.</li></ul>