A knob at the end of a cannon, cast onto the gun breech, to which a heavy rope is attached in order to control recoil.
A small, round, hot variety of chili pepper, Capsicum annuum, which rattles when dry.
A bell attached to a sleigh or sleigh harness.
A bar or shaft with an aperture for a bolt or threaded rod to attach to or pass through.
An insane person, a crazy person, a madwoman or madman.
Crazy, mad.