- a flag that is all or mostly black, esp. such a flag flown by a pirate ship
- in auto racing, a signal to a driver during a race, made by waving a solid black flag, indicating that the driver must stop and consult an official
See black flag in American Heritage Dictionary 4
transitive verb black-flagged
, black-flags Sports
To signal (the driver of a racing car) to proceed immediately to the pits.
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