snake in the grass

noun

1. a treacherous person, especially one who feigns friendship.
2. a concealed danger.

Word History and Origins

Origin of snake in the grass¹

First recorded in 1690–1700

Idioms and Phrases

A treacherous person, as in Ben secretly applied for the same job as his best friend; no one knew he was such a snake in the grass . This metaphor for treachery, alluding to a poisonous snake concealed in tall grass, was used in 37 b.c. by the Roman poet Virgil ( latet anguis in herba ). It was first recorded in English in 1696 as the title of a book by Charles Leslie.

Example Sentences

We cruise down highways 29 and 41 in Naples, driving no faster than 25 miles per hour as she looks for snakes in the grass.

From National Geographic

"You've got to be on the lookout for the snakes in the grass."

From BBC

No small part of the bouncy charm of “Oliver!” is that the snakes in the grass have all the lines.

From Los Angeles Times

“Why is it that the screen Chinese is nearly always the villain of the piece, and so cruel a villain-murderous, treacherous, a snake in the grass. We are not like that.”

From Los Angeles Times

“Why is it that the screen Chinese is nearly always the villain of the piece, and so cruel a villain — murderous, treacherous, a snake in the grass,” she told the Los Angeles Times in 1933.

From Washington Times