These two characters combine to mean “Great Hero.” The `大 (dà)` acts as an amplifier, elevating a standard hero `侠 (xiá)` to someone of legendary status and immense respect.
The concept of `大侠` is inseparable from the genre of `武侠 (wǔxiá)`, which literally means “martial-chivalry.” These are the epic stories of martial artists in ancient China, found in novels, films, TV shows, and video games. A `大侠` operates within a world called the `江湖 (jiānghú)`, literally “rivers and lakes.” The `江湖` is a parallel society of martial artists, clans, sects, and outlaws, existing with its own rules and code of ethics, largely independent of the imperial government. Comparison to a Western “Knight”: A Western knight is typically part of a feudal system, sworn to a king or lord, and often a member of the aristocracy. A `大侠`, in contrast, is almost always a free agent. Their loyalty is not to a ruler—who is often depicted as corrupt or ineffective—but to their own conscience and the principle of `侠义 (xiáyì)` (righteous chivalry). They are often figures of the common people, sometimes even outlaws in the eyes of the state, who represent a higher, more personal form of justice. While a knight upholds the law of the land, a `大侠` upholds a moral law that transcends it.
While the era of wandering swordsmen is over, the term `大侠` is very much alive in modern Mandarin, often used with a tone of respect and sometimes a bit of playful exaggeration.
The most common mistake for English speakers is to confuse `大侠 (dàxiá)` with the general word for “hero,” `英雄 (yīngxióng)`.