Definition

1. Noun:
   • A warning sign or signal of danger, a problem, or a reason for caution: A "red flag" is something that indicates a potential issue or threat, suggesting that one should stop, reconsider, or investigate further.
   • A symbol of socialist or communist revolution: Historically, a "red flag" has been used as the emblem of leftist revolutionary movements.
   • A literal red-colored flag used as a signal: A physical flag, often red, used to communicate a specific warning, such as dangerous swimming conditions.

Usage Examples

• As a warning sign:
  • His history of angry outbursts was a major red flag for the hiring committee.
  • Not having a clear business plan is a red flag for potential investors.
• As a symbol of revolution:
  • The protesters marched through the streets carrying the red flag.
• As a literal warning signal:
  • Lifeguards raised the red flag to warn swimmers of the strong currents.

Advanced Usage

• "to raise a red flag": To bring a warning sign to someone's attention.
  • The auditor's report raised several red flags about the company's finances.
• "a red flag law": A specific type of law, often regarding gun control, that allows courts to order the temporary removal of firearms from a person deemed to be a danger.
  • The state recently passed a red flag law to help prevent gun violence.

Variants and Related Words

• Red-flag (verb): To mark or identify something as being problematic or worthy of attention.
  • The system automatically red-flags any transaction over $10,000.
• Red-flagging (noun): The act of identifying warnings or problems.

Synonyms

• Warning sign
• Caution signal
• Alarm bell

Related Idioms and Phrases

• "like waving a red flag at/for a bull": To do something that is certain to provoke an angry or violent reaction.
  • Criticizing his work in front of his team was like waving a red flag at a bull.

Noun

1. something that irritates or demands immediate action
   • doing that is like waving a red flag in front of a bull
2. the emblem of socialist revolution
3. a flag that serves as a warning signal
   • we didn't swim at the beach because the red flag was up