black flag

plural black flags

1. Any flag that has a black, or predominantly black, color, (especially):
   1. literallyA flag with a black color, used as a symbol of anarchism.
   2. literallyhobbiesA racing flag with a black color, used in auto racing to summon a driver to the pits or to signal disqualification.
2. figurativelyinformalA cue, warning, or alert; a sign or signal that something is extremely wrong, often something criminal, hideous or atrocious; a extreme red flag.

present singular third person black flags · participle present black flagging · participle past black flagged · past black flagged

1. transitiveTo summon (a racing driver) to the pits by waving a black flag.

   When a driver is black-flagged, he knows it.

   2000, Mark Martin, NASCAR For Dummies, page 87

   1 more example

   Jack Sears was driving the famous John Willment Cobra roadster "39PH." Sears was black flagged, and after returning to the track, drove a race that is still talked about today.

   1994, Shelby Cobra, page 112