Definition of water rattler in English:

water rattler

noun

US
  • 1The eastern diamondback rattlesnake, Crotalus adamanteus (now rare).

  • 2Any of several non-venomous water snakes thought to resemble this, especially the brown water snake, Nerodia taxispilota.

Origin

Late 19th century; earliest use found in John Sterling Kingsley (1854–1929).