yellow flag

American  

noun

1. Nautical. quarantine flag.

2. water flag.

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yellow flag British  

noun

1. another name for quarantine flag

2. See flag 3

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Etymology

Origin of yellow flag

First recorded in 1775–85

Example Sentences

Hlyten's relative, fellow Ukrainian Arkady Dolina, stood nearby with a large blue and yellow flag draped over his shoulders at the event.

From Barron's • Apr. 23, 2026

The red flag with central yellow star stayed official in the home country, while the Southern yellow flag with three red stripes became a refugee reminder in the United States.

From Salon • Dec. 31, 2025

But if that should fall to the S&P 500 median of 10 times, it “would raise a yellow flag that debt payments are becoming burdensome,” says Emanuel.

From MarketWatch • Dec. 29, 2025

He was unlucky to catch a brief yellow flag in the first part of qualifying.

From BBC • Sep. 15, 2024

‘You dressed in black,’ Nico noted, ‘with the sun coming up. You painted your face but didn’t cover that mop of blond hair. You might as well be waving a yellow flag.’

From "Blood of Olympus" by Rick Riordan