rat snake

any of several New and Old World colubrid snakes, of the genus Elaphe, that feed chiefly on small mammals and birds.

Also called house snake.

Origin of rat snake

First recorded in 1855–60

All the roofs of the thatched bungalows swarm with rats, and in every house is kept a rat-snake, which kills and eats these rats.

A Voyage in the 'Sunbeam' |Annie Allnut Brassey
A friend informs us that he once saw in these gardens a rat-snake of Ceylon devour a common Coluber natrix.

Curiosities of Civilization |Andrew Wynter
The presence of a rat-snake (Zamenis mucosus) in a house at night is believed to bring good fortune to the inmates.

Omens and Superstitions of Southern India |Edgar Thurston
A person should postpone an errand on which he is starting, if he sees a cobra or rat-snake.

Omens and Superstitions of Southern India |Edgar Thurston

One the great serpent would select, would lap in scaly coils, crush to a red pulp and swallow as a rat-snake swallows a mouse.

The Hour of the Dragon |Robert E. Howard

rat snake

any of various nonvenomous rodent-eating colubrid snakes, such as Elaphe obsoleta of North America and Ptyas mucosus of Asia