red flag (suomeksi)

Määritelmät:

(lb, en, idiomatic) A cue, warning, or alert; a sign or signal that something is wrong.
(lb, en, rail) In the United Kingdom and some other countries, a flag formerly used by a railway guard to warn the driver not to start the train.
(lb, en, politics) A common symbol, usually in the form of a banner, for leftist revolutionary ideologies, especially socialism.