snake in the grass

American  

noun

1. a treacherous person, especially one who feigns friendship.

2. a concealed danger.

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snake in the grass Idioms  

1. 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.

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Etymology

Origin of snake in the grass

First recorded in 1690–1700

Example Sentences

Franklin was uncompromising and often dismissive, but it is Watson who emerges as the snake in the grass.

From Washington Post • Nov. 11, 2021

“Clearly Doug is a snake in the grass and hopefully the Federal Trade Commission hammers him,” one member of the group wrote.

From The Verge • Mar. 4, 2020

That temptation to stake a claim, to occupy valuable space, is the slithering snake in the grass that’s making everyone in Eden bonkers.

From New York Times • May 10, 2013

He called him a "rattlesnake" and a "snake in the grass".

From The Guardian • Jan. 18, 2013

Thinking he’d been spooked by a snake in the grass, I whispered, “What do you see?”

From "Worth" by A. LaFaye