red_flag has definitions from the field of psychology
1
[ noun ] (psychology) the emblem of socialist revolution

Related terms

emblem

2
[ noun ] a flag that serves as a warning signal

Examples

"we didn't swim at the beach because the red flag was up"

Related terms

flag alarm

3
[ noun ] something that irritates or demands immediate action

Examples

"doing that is like waving a red flag in front of a bull"

Related terms

annoyance

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