n.

1. 扣鏈齒
2. 扣鏈齒輪
   The sprocket chain on my motorcycle broke loose, and I am trying to fix it.

   我的摩托車上的扣鏈齒輪鬆脫了，我正在想辦法修理。

n.

1. each of several projections on the rim of a wheel that engage with the links of a chain or with holes in film, tape, or paper.
2. (also sprocket wheel) a wheel with projections of this kind.