spy on

Idioms  

1. Secretly or furtively observe someone or something, as in The children loved spying on the grownups, or The company sent him to spy on the competitor's sales force. [Early 1600s]

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Example Sentences

“Havana Affair” has a lively espionage theme: “Sent to spy on a Cuban talent show / First stop Havana go-go.”

From The Wall Street Journal • Apr. 27, 2026

Yuen denied commissioning Wai to carry out surveillance of Hong Kong dissidents based in London, including "never" having asked him to spy on pro-democracy activist Nathan Law.

From BBC • Mar. 23, 2026

For much of this century, the big tech companies, as well as their investors, have often tried to avoid developing or promoting things that helped spy on people or kill them.

From Los Angeles Times • Mar. 20, 2026

There have also been protests by activists who fear the sprawling site in the historic former Royal Mint, next to the Tower of London, could be used to spy on and harass dissidents.

From Barron's • Jan. 26, 2026

Werfel felt like he should say something nice so that Spurge would feel better about himself, but that didn’t really make sense, seeing as the elf had been trying to spy on Werfel’s people.

From "The Assassination of Brangwain Spurge" by M.T. Anderson and Eugene Yelchin

Related Words

• stalk