赤旗

(1)something that irritates or demands immediate action; "doing that is like waving a red flag in front of a bull"

(2)いらだたせる、または即座の行動を要求するもの

(3)a flag that serves as a warning signal; "we didn't swim at the beach because the red flag was up"

(4)警報として機能する旗

(1)