surveil

American  

[ser-veyl] / sərˈveɪl /

verb (used with object)

surveilled, surveilling

1. to place under surveillance.

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surveil British  

/ sɜːˈveɪl /

verb

1. to observe closely the activities of (a person or group)

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Etymology

Origin of surveil

First recorded in 1965–70; back formation from surveillance

Explanation

To surveil is to spy on someone, the way a television private eye sits in her car and uses binoculars to surveil the show's villain. The noun surveillance came first, from the French surveiller, "to oversee or watch." If you were to surveil someone, you'd keep a close eye on them, monitoring everything they do. These days, that means keeping track of their online activity as well as their phone calls and physical movement. It's usually authority and governmental figures doing the surveillance — although if a company wants to sell you something, they just might surveil your internet history.

Example Sentences

Anthropic doesn’t want its products used to surveil Americans or create autonomous machines of war.

From Slate • Feb. 27, 2026

The document outlines the myriad ways the country’s security agents would try to surveil, entrap, compromise and recruit American visitors.

From The Wall Street Journal • Dec. 20, 2025

They fear the site could be used to surveil and harass dissidents.

From Barron's • Dec. 2, 2025

"Drones lower the political and operational threshold for action, providing options to surveil and strike while trying to reduce escalation risks," says Prof Matisek.

From BBC • May 9, 2025

In the early days, he had posed as a homeless person to surveil militia training facilities, but he decided that was a waste of time.

From Salon • Jan. 7, 2025