cannelure

n.物体表面之细槽

A groove or channel in a surface, often one that is circular or semicircular, such as the indentation on a bullet or the groove on the edge of a coin;

名词；

1. The cannelure on the bullet helps improve stability during flight.
子弹上的凹槽有助于提高飞行的稳定性。
2. The cannelure on the coin makes it easier to grip and handle.
硬币边缘的凹槽使得抓握和操作更加方便。