What is Neba in Japanese Katana terminology?

"""Neba"" (寝刃) refers to the process of enhancing the cutting ability of a finely polished sword. When a finely polished sword is used to cut fibrous objects (such as clothing), the blade may slip. Therefore, it becomes necessary to create a saw-like finish on the blade edge with fine serrations to increase the sword's cutting ability. This process is referred to as ""Neba o awaseru"" (寝刃を合わせる).

This practice reflects the high level of skill and attention to detail required in sword making. The creation of fine serrations on the blade edge enhances the sword's cutting ability, making it more effective for cutting fibrous objects. This underscores the importance of proper maintenance in preserving the quality and effectiveness of a sword."