Caudimordax is the Latin name of "Tailbiter", the sword of Farmer Giles. The sword cannot be sheathed when a dragon comes within five miles of its bearer's presence. Four generations earlier, the sword belonged to Bellomarius, "the greatest of all the dragon-slayers" in the Middle Kingdom. Farmer Giles is granted this antiquated sword—by then become unfashionable—as a reward for driving off a giant from his fields with his blunderbuss. He later uses the sword to capture and control the dragon.
Read more about this topic: Farmer Giles Of Ham