The word **光亮** is a typical Chinese compound word formed through **coordinative (parallel) morphology**, where two semantically similar or related characters are combined to create a new, nuanced meaning. The first character, **光** (guāng), primarily means "light" or "radiance," while the second, **亮** (liàng), means "bright" or "luminous." By joining these two synonyms, the compound **光亮** reinforces and intensifies the core concept, resulting in a word that means "bright light" or "brightness," often conveying a sense of clear, shining illumination. This structure allows it to function flexibly as both a noun (e.g., "a light") and an adjective (e.g., "bright").