The term "dragon sword" can refer to different things depending on the context. It is a broad term used in various mythologies, folklore, and fictional settings. Here are a few notable examples:

1. Dragon Sword in Chinese Mythology: In Chinese mythology, the Dragon Sword, also known as the Longquan Sword, is a legendary weapon associated with dragons. It is said to be a powerful and revered sword crafted by skilled blacksmiths. The Dragon Sword is often depicted as having a unique and intricate design, representing the strength and mythical qualities of dragons.
2. Dragon Slayer's Sword in Western Folklore: In Western folklore and fantasy settings, a "dragon slayer's sword" or a sword specifically designed to slay dragons is sometimes referred to as a dragon sword. These swords are typically depicted as exceptionally sharp, strong, and often enchanted with properties that enable them to defeat or harm dragons.
3. Dragonblade in Video Games and Fantasy Media: The term "dragon sword" is also used in various video games, books, and movies to refer to specific fictional swords with dragon-related themes or powers. These dragon swords are often unique artifacts or weapons associated with dragons, possessing magical properties, elemental abilities, or the ability to harness dragon-related energies.

It's important to note that the concept of a dragon sword can vary widely depending on the specific mythology, folklore, or fictional setting. The design, powers, and significance of a dragon sword are typically determined by the creative interpretation of the particular story or fantasy world in which it appears.