A tooth or tongue, also called a pawl or a click, which drops into the notches of a toothed wheel and prevents it from turning backward.

棘轮上之掣子。

The toothed wheel.

棘轮。

The toothed wheel and the pawl, working together.

棘轮与掣子所构成之机械。

Same as ratch.

亦可作 ratch。