Definition of "Rattle" :

noun: loosely connected horny sections at the end of a rattlesnake's tail

noun: a baby's toy that makes percussive noises when shaken

noun: a rapid series of short loud sounds (as might be heard with a stethoscope in some types of respiratory disorders)

"The death rattle."

verb: shake and cause to make a rattling noise

verb: make short successive sounds