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milk snake

noun
  1. any of numerous, usually brightly marked king snakes of the subspecies Lampropeltis triangulum (doliata), of North America.

Origin of milk snake

An Americanism dating back to 1790–1800; so called because they were said to suck milk from cows
Also called house snake, milk adder.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for milk adder

milk snake

noun
  1. a nonvenomous brown-and-grey North American colubrid snake Lampropeltis doliata, related to the king snakes
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012