Rattlebox \Rat"tle*box`\, n.

1. A toy that makes a rattle sound; a rattle.

2. (Bot.)
   (a) An American herb (Crotalaria sagittalis), the seeds of which, when ripe, rattle in the inflated pod.
   (b) Any species of Crotalaria, a genus of yellow-flowered herbs, with inflated, many-seeded pods.

Source: Webster's Revised Unabridged Dictionary (1913)