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

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

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

From Literature

The kids caught snakes in the grass, and the men caught salmon in the creek.

From Salon