What is Tameshimei in Japanese Katana terminology?

"Tameshimei" (試し銘) refers to an inscription on a sword that records the results of testing the sword's cutting ability by cutting through criminals or other objects. This served as a guarantee of the sword's sharpness. If the sword was able to cut through two stacked bodies of executed criminals, it was recorded as ""Futatsudo"" (二つ胴), and if it cut through three bodies, it was recorded as ""Mitsudo"" (三つ胴).

The fact that this practice is often seen in swords from the Shinto period onwards is believed to be related to the decrease in actual combat during the Edo period, which resulted in fewer opportunities to test the cutting ability of newly made swords.

This practice reflects the high standards of sword making during these periods. The ability to cut through multiple bodies would have been a testament to the sword's sharpness and cutting ability. The inscription of these results on the sword served as a guarantee of its quality, adding to its value and prestige. The decrease in actual combat during the Edo period underscores the changing circumstances of the samurai class and the evolving role of the sword."