on the lookout

Idioms  

1. Also, on the watch. Vigilant, alert, as in Be on the lookout for the twins—they're somewhere on this playground, or He was on the watch for her arrival. Both phrases were originally used with upon. Upon the lookout was originally nautical usage, meaning “on duty being watchful” (as for another ship, rocks, or land); it appeared in the mid-1700s, and on replaced upon about a century later. Upon the watch was first recorded in Daniel Defoe's Robinson Crusoe (1719), and on the watch in Jane Austen's Sense and Sensibility (1797).

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Example Sentences

But with Dodger Stadium, the marine layer angle jumped out at me because I’m always on the lookout for relatable ways to tell the climate change story.

From Los Angeles Times • Jun. 18, 2026

Jarvis and Sir Keir are also on the lookout for a new armed forces minister, after the bizarre resignation of Al Carns.

From BBC • Jun. 12, 2026

Rio is also still on the lookout for copper assets, which could prove to be expensive, the analysts say.

From The Wall Street Journal • Jun. 3, 2026

They will also be on the lookout for possible flashes of light caused by meteorites crashing into the surface of the Moon.

From Barron's • Apr. 5, 2026

“Stay sharp, lads. The Magistrate said to be on the lookout for any funny stuff.”

From "Dactyl Hill Squad" by Daniel José Older

Related Words

• active
• bright
• careful
• intelligent
• observant
• perceptive
• sharp
• vigilant
• wary
• watchful
• wired
• wise