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

But the Australian felt strong in the final session in Las Vegas, only to come across a yellow flag on his final run and have to back off.

From BBC

He was summoned to see the stewards for allegedly failing to slow under double yellow flags waved when team-mate Charles Leclerc spun late in the second sprint qualifying session.

From Barron's

Hamilton also faces an investigation for failing to slow sufficiently for the yellow flags waved when Leclerc lost control.

From BBC

Maine currently has a “yellow flag” law that gives authorities a way to confiscate guns from a person who’s dangerous or suicidal.

From The Wall Street Journal

“As bubble fears have begun to pick up, this is one of the few yellow flags we’ve seen in the space.”

From Barron's