rattle (v.) Look up rattle at Dictionary.com
early 14c., perhaps in Old English, but not recorded; if not, from Middle Dutch ratelen, probably of imitative origin (cf. German rasseln "to rattle," Greek kradao "I rattle"). Sense of "fluster" is first recorded 1869. Related: Rattled; rattling.
rattle (n.) Look up rattle at Dictionary.com
c.1500, in reference to the sound, from rattle (v.). As a child's toy, recorded from 1510s.